Best Practices


Chingchai’s Method for Curing New Live Rock

You need the following equipment:
– suitable size container (plastic garbage cans work well)
– protein skimmer (it will get a major workout)
– powerheads
– good quality salt mix
– a small scrub brush
– ammonia, nitrite, nitrate test kits

The basic method is as follows:
– scrub off any sponges and soft corals that have turned black
– water should have pH at 8.2-8.4 and S.G. at 1.023-1.025
– no lights for 7-10 days to avoid an algae bloom (high nutrients)
– keep water heated (74-80F°)
– do not do any water changes until Ammonia and Nitrites tests both read zero. Then do a 50-75% water change, vacuuming up as much loose sediment as possible.
– provide plenty of water movement within the container (powerheads)
– provide plenty of oxygenation in the water (done by skimmer which will need frequent cleaning)

The curing process will take 2-4 weeks depending on the amount of die-off on your rock and the effectiveness of your protein skimmer.

A simple but very effective treatment for eliminating unwanted critters in your Live Rock is to dip each piece in a bucket of very saline water (SG 1.030) for a few moments. Mantis shrimp will quickly
evacuate the rock. Bristle worms will also crawl out and can be pulled from their holes with a pair of tweezers.


Mr.Wilson’s Method for Treating New Live Rock


Rubber gloves
Narrow screw driver
A coupe of schooners


Remove each rock one by one and shake them in a tub of water. This will remove the loose detritus. Treat all crabs as parasites, as very very few are friendly (commensal/symbiotic). Most of the worms you will encounter are harmless, but there will be no shortage of worms in the long run, so go ahead and remove any loose ones that may be injured. If they are healthy, they will be deep in the rock. Shake the hell out of it. Upside down and in every direction. I use a plastic vegetable scrub brush to loosen large deposits of detritus. I should have stressed the rubber gloves more as well. There are lots of stinging worms that will leave nematocysts (cactus needle-like stingers) in your fingers. I managed to get blood poisoning once from handling live rock without gloves.

Throw any snails you see into a bucket of saltwater and use your new macro lens to get some free identification on here. Watch for mantis shrimp (Google it). They are easy to identify once you know what you are looking for. Yes, kill them.

I would use the established saltwater the rock is in now for the rinsing process. Freshwater rinsing is more for corals that may have parasitic hitchhikers. Live rock is less likely to carry bad guys than live corals are. In the case of live corals, freshwater dips and a bath in an oxidizer such as Lugol’s iodine or potassium permanganate. The water at the bottom of your vats will be turbid/dirty, so make sure you set aside cleaner rinsing water as you work through the vats.

Any sponges, sea squirts, or other invertebrates that have made it this far are hardy and should be left alone. Only new rock should have the sponges and algae removed from it. It is a good idea to reverse the stacking order of the rock as you put it in a new container, so the rock that was at the bottom is now at the top.

Siphon or shopvac the junk off of the bottom of the vats. Remember to elevate the rock on milk crates to provide a buffer zone for crabs, worms and other questionable hitchhikers.

After the rock has been acclimated for two weeks and you have not experienced a significant die-off, you can proceed to introduce a 6 hour photoperiod with somewhat diffused light. If your lighting is greater than 250 watt MHL, then suspend it two feet above the rock. Otherwise, a 250 watt MHL a foot above the water surface should be fine with a 6 hour photoperiod (day). Slowly move the photoperiod up to 8 hours per day over the next two weeks. Watch for diatom algae (brown slime). It will come and go in about two weeks, then you will get green slime algae (cyanobacteria). This too will pass in another month, give or take.

Start monitoring calcium, magnesium, and carbonate hardness levels. Maintaining these at optimum levels will foster the growth of coralline algae.

It’s also a good idea to start sorting rock sizes and shapes so you can have a better handle on your building blocks when you commence with the aquascaping. You don’t want to get down to the bottom of the last vat and find those show size rocks you ordered.

Now that you are sure that your rock has no die-off, you should add ammonium chloride (not household ammonia/ammonium hydroxide) to feed the nitrifying bacteria (nitrogen cycle).

You can simulate a bioload by adding 0.01 grams of ammonium chloride (dry crystals) per gallon of water. This will give you an ammonia level of 1ppm. Check the ammonia level to make sure you got the dose right. Depending on how much of a filter bed you have already established, it will take one day or several for the ammonia to go down to zero. When it hits zero, add a slightly higher dose (0.015 grams/gallon) to render an ammonia level of 1.5ppm. Continue to dose at this level until you start stocking the tank. The livestock will supply all the ammonia you need for the nitrogen cycle.

You will start to see nitrite as soon as the nitrifying bacteria converts the ammonia. It is safe to add livestock once the rock is able to maintain nitrite at zero while you are dosing ammonia, which may take a few weeks depending on your rocks bacterial biodiversity/filtering capacity. Nitrate will start to show in tests after a few weeks of nitrite reduction. The family of bacteria that assimilate nitrate take the longest to establish. Once you have established nitrates below 10 ppm you can start adding sps corals. At this point in time phosphates will be a concern. Throughout this cycling process you need to monitor pH as it may drop with heavy bacterial growth.

Alternatively you can use livestock to feed the nitrogen cycle but it puts a lot of stress on the organisms you use and it is more of a shotgun dosing system. The chemical route is faster and safer.

Dose the ammonium chloride while the rock is still in the holding tanks as it is the rock you are feeding, not the water or filtration devices lying around.

It would be beneficial if you can do the same with the sand. The denitrifying bacteria that consumes nitrate does not even begin to form until the bacteria that converts ammonia to nitrite, and in turn nitrite into nitrate has developed.

Denitrification (nitrate reduction) is the main goal with sand beds. As I mentioned earlier, this process takes awhile and is the last to start if you don’t treat the tank chemically (ammonia).

Start dosing lightly to be sure of the concentration of the ammonium chloride. You may also mess up the math with displacement etc. An ammonia test kit will assure you end up with the 1 ppm ammonia level you need.

If your rock hasn’t been starved of nitrogen, it will reduce the ammonia quickly (in a day or two). If the water has been nitrogen poor, it will take as long as a week for the ammonia spike to drop to zero.

All your rock needs now is nitrogen (ammonia) and good water flow for oxygen. The biological filtration process is working independent of your protein skimmers and whatever else you are currently using with the rock. If you keep the bacteria on the rock fed and monitor it with test kits, it will jump start your display and fish room. You will not get the diatom algae and green slime algae blooms that you traditionally get. You can also turn your lights and protein skimmer on earlier in the process (right away instead of a few weeks down the road).

Some people use raw organic sources of nitrogen like dead shrimp to inoculate their tanks, but it’s hard to dose and monitor ammonia reduction/conversion. The dead shrimp takes a few days to decay and release ammonia along with protein. It also introduces phosphates and heavy metals that you have no means of assimilating or removing.

Your LFS will have ammonium chloride. Dry crystals are the most accurate, as liquid tends to evaporate and range in concentration.


More From Mr.Wilson On Acclimating New Live Rock

Everyone has their own system for acclimating live rock. Most retail stores use a spray system where the rock remains exposed to the air. While this system does flush out crabs and worms and increases nitrification due to the added oxygen, I prefer an ebb and flow system whereby the vat fills and drains in cycles. This works well with two vats. As one fills, the other drains.

Elevating the rock on milk crates to separate crabs and detritus is a good idea. I used to keep the rock in milk crates so I could shake out detritus every few days. Setting up a power washer with saltwater works well for really dirty rock.

If you got an ozonizer with the RK2 protein skimmer you should hook it up to the temporary skimmers you have for the rock. Better still, drag the RK2 over to the vats. You don’t need or want a protein skimmer on the tank when it’s cycling, but the rock needs it now more than ever.

It’s only monster tanks like Peter’s that require the live rock to be acclimated in dedicated remote vats/tanks/tubs. If your tank is under 500 gallons, you can add the rock directly to the tank dry, spraying or splashing water on it periodically as you work.

I drill some rocks and place them over a PVC pipe skeleton. I also use an aragocrete cement mix to bond the rocks. This requires a day for the cement to set. Wrapping the rocks in wet newspaper or towels is enough to keep it alive. The cement causes a temporary pH & calcium increase and the rock needs a few weeks to get its “sea legs” so the rock acclimation process is carried out in the display tank.

As a general rule, I recommend that you purchase cured rock and let the local fish store go through the hassle. The added benefit is you can pick and choose your rocks according to your needs and what is available. Peter’s rock is direct from the source so it requires a few more precautions. It’s also hard to change 1200 gallons of water every week

In summary, as long as the rock is kept damp, it will remain healthy. From a nitrification/bacterial standpoint, damp rock is healthier than wet/submerged rock during acclimation. The various toxic forms of nitrogen (ammonia, nitrite, and to a lesser extent nitrate) are not an issue if the rock isn’t submerged in water. This is also true of oxygen and other gas levels.

I never liked the term “cooking live rock”. The term itself implies that you are sterilizing the rock. If you want to kill all of the good organisms in order to kill a few potential bad organisms, then the most efficient way to achieve this would be to bleach the rock, then dechlorinate it two hours later. The problem with going this route is you extend the cycling period from weeks to months and in the process, a lack of beneficial organisms leaves room for more opportunistic pests (cyanobacteria, diatom algae and dinoflagellates) to get a foothold. This drastic method of “cooking” leads me to wonder why you wouldn’t just use dead rock or portland cement-based aragocrete.

The other definition of “cooking” I’ve heard thrown around is the process of keeping the rock in the dark for a few months to kill off nuisance algae. It seems silly to me as a low nutrient tank will not have nuisance algae, so the problem isn’t the rock, but the water quality. The usual suspects we know as “reef parasites” are not photosynthetic so depriving them of light will do nothing for the cause.

Many of the reef parasites we encounter come from corals, and not from the rock so drastic measures in rock acclimating are often moot. As long as you have removed all crabs, mantis shrimp, and nudibranchs (sea slugs) you’re covered. There are a few macro algae species that can proliferate and take over, but there are chemical (1500 mg magnesium) and biological (herbivorous fish & inverts) methods of keeping them in check. Parasitic worms such as “red bugs” and flatworms enter the tank as hitchhikers on their coral hosts, and can be treated with dewormers like praziquantel (droncit), piperazine (entacyl), ivermectin or trichlorfon (dylox) .

In my opinion, the primary goal in live rock acclimation is to biologically assimilate the massive die off of macro organisms on the surface of the rock, and the greater die off of micro organisms within the rock. I know first hand from drilling core holes in live rock that there are large burrowing urchins and burrowing snails and nudibranchs deep inside the rock. It looks like Peter has made it through this critical die-off period and has done so without compromising coralline algae. This isn’t to say that coralline algae won’t grow on dead or artificial rock, as it will in about six months. It’s just an indicator of a broad biodiversity of life … more good than bad.


Mr.Wilson’s Checklist for Quarantine Tanks and Hospital Tanks

My checklist for a quarantine tank (QT) or hospital tank (HT). QT & HT is a matter of quality rather than quantity. You need enough room for tangs and those impulse buys, but less is more in most cases as water changes and medications go farther. You don’t have to follow all of my suggestions, just use it as a guideline. Due to the scope of the post, I have excluded medication dosage and handling practices.

1) A lid to keep in and deter jumpers:

You can use glass, egg-crate, or fiberglass screen. Wrasse and gobies are far more likely to jump in a small empty QT/HT tank. PVC pipe and fitting hiding places are best as they are inert, non-calcareous (no calcium structure to absorb medications), easy to clean and sterilize, and smooth so they won’t damage fish as they scratch their parasites off. Using a dim nightlight will minimize the stress of the lights coming on and off instantly and reduce shock to jumpers. Some fish can thread themselves through a needle so be sure to cover every possible exit hole in the lid, as they will find it.

2) A dedicated heater with a reliable thermostat:

A heater is much more important to a QT/HT than in a display tank because you are dealing with a much smaller volume of water and fewer pieces of equipment that add heat. Stability in temperature is more important than the actual temperature. Unlike freshwater ich, marine ich (Cryptocaryon & Oodinium) is cued by temperature increases rather than decreases. Having said that, an elevated temperature (84-86°F) will speed the life cycle of ich to 10 days rather than 14. This is good news if the water is medicated and bad news if it is not. Let’s assume you have a treatment regimen that is steadily reducing the population of free-swimming ich in the tank by 80% per generation. A shorter life cycle of 10 days will assure that you can eradicate the ich quicker as the population shrinks with each consecutive generation as they enter the swimming stage of their life cycle. If you are not treating the water with ich medications, the parasite population will increase with every consecutive generation, so a shorter life cycle will assure a quicker demise of your fish.

3) Indirect, diffused light:

Try to keep a ten hour photo-period to reduce stress. Many antibiotics are photo-degradable, so direct light should be avoided. Deep water fish like certain anthias do not adapt to bright aquarium lighting.

4) A biological filter:

This can be a bio-wheel or canister filter that is normally run on the display tank to keep it cycled. It is too small to adversely affect the display tank. Remember not to use carbon as it will remove medications. Alternatively, you could just store the filter media in the display tank’s sump to keep the bacteria viable. Running the biofilter on a QT/HT with no bioload will slowly kill off the beneficial nitrifying bacteria that you need to control the nitrogen cycle. Biofilters have fallen out of fashion with reef tanks but they are still vital with QT/HT.

Copper will adhere to a biowheel. Using a new biowheel each time would be costly but cheaper than losing fish.

I would use a copper remover like Cuprisorb with carbon to remove the residual copper. It’s a good practice to remove old copper from the QT so you are starting fresh each time. It makes dosing safer. It’s the calcareous (calcium-based) materials that absorb copper that you need to watch out for. This is less of any issue with ionic or chelated copper. If you’re really paranoid about copper, soak it in RO/DI water and test for copper.

You could dose the QT with ammonia when you anticipate the addition of new fish, but who are we kidding? These are impulse buys. Depending on the style of bio-filter, you could incorporate your filter floss or sponge from the display’s mechanical filter into the filter. HOT (hang on tank) filters are good for this.

You can also do a water change and add fresh display water to the QT so it has some beneficial bacteria. The nitrifying bacteria grow on detritus in the substrate so you don’t need to prefilter the old water before adding it to the QT.

In commercial QT they often employ air-driven sponge filters. These sponges can be stored in the filter of the display tank and moved to the QT filter as needed. It’s all about conditioning the bacteria. Nitrifying bacteria reproduce faster when the temperature swings (lag) so they won’t be harmed going to the cooler QT water. What ever you do, don’t rinse the filter media or disturb it as the delicate biofilms can be lost.

5) Plastic cups to catch and move fish:

Unlike freshwater fish, marine fish haven’t adapted to breathing atmospheric air even for a brief period of time. Most secondary bacterial infections are caused by fish net abrasions. Reef fish have tiny delicate scales that are easily bruised or removed. A trip to the Dollar Store is in order.

6) An ultraviolet (UV) sterilizer:

They cost a couple hundred dollars but they will pay for themselves after they save a few fish. The bulb will last a long time as it will only be used while you have fish in the QT. You could borrow a UV sterilizer from the display tank without causing too much trouble. UV sterilization should be discontinued if you are using antibiotics. Copper sulphate, formalin, malachite green, and methylene blue are not significantly affected by UV irradiation. Ionic copper such as Mardel’s Coppersafe and Seachems’s Cupramine become more toxic as the chemical bond is broken by UV, so UV should be discontinued or copper sulphate should be dosed in its place daily to maintain a safe therapeutic level of 0.20 ppm. If you are running a series of QT/HT tanks, a properly sized UV unit assures that a 100% kill ratio occurs so diseases can be contained to individual tanks.

7) A good camera:

A camera will help you take pictures to submit for help in diagnosis and treatment. They are also handy in picking up defects in the fins and scales that you may miss with the human eye. You can zoom in on your photo in Photoshop for a really close inspection without the fish moving. While you are there you can Photoshop any missing scales and torn fins for a virtual recovery. 😉

8) Low salinity (hyposlainity) of 1.013 (HT) to 1.018 (QT):

Stressed marine fish can dehydrate when placed in standard salinity water (1.023+). They don’t have a healthy slime coat to regulate osmotic pressure and have to work a lot harder to pump salts out of their bodies. A lower salinity will also slow fish metabolism and kill parasites. Ammonia is also less toxic at a lower salinity as well. Fish adapt well to being moved to water with a lower salinity. They adapt poorly to moves to higher salinity so slowly reintroduce them to display tank water of 1.025 salinity. In cases of oodinium the salinity can be lowered to 1.013 but for no longer than 10 days. A salinity of 1.017 can be maintained for three weeks while the fish is developing a healthy slime coat.

9) Premixed saltwater:

Use display tank water for QT/HT water changes. Add new saltwater to the display. This will remove nitrogen compounds from the QT/HT and supply fresh pro-biotics and micro-organisms that will out-compete pathogens. The quarantined fish will be acclimated to the display tank water at all times, with the exception to the lower salinity. You can add fresh RO/DI water accordingly to correct/lower the salinity. Remember to top-off medications when you adjust salinity. One week before moving the QT/HT fish to the display tank, you can start adding more display tank water to slowly raise the salinity to avoid osmotic shock. Moving the fish to a safe zone in the sump assures you can monitor feeding, let the other fish get used to the “smell” of the new fish, and allow you to catch it if it gets sick again.

10) Large PVC pipe segments for hiding places:

Paint the back and side walls to provide additional shelter. Reef fish do poorly if they don’t have hiding places.

11) Household bleach (sodium hypochlorite):

If a disease breaks out, sterilize the tank with bleach before re-use. Make sure it is pure sodium hypochlorite with no fabric softener or scents added. You can also buy chlorine (bleach) from pool supply shops. You can use a 20% bleach treatment for a few hours, then change 100% of the water and dechlorinate the new water with sodium thiosulphate or a commercially prepared dechlorinator like Seachem’s Prime. I prefer Prime because it detoxifies both ammonia and nitrite. Prime should be on hand in large quantity for emergencies. Do not use too much bleach as it can damage some equipment such as fish nets and brittle plastics. A more gentle alternative would be to use hydrogen peroxide as it leaves only water and oxygen as residuals.

12) Five gallon bucket for fish & coral dips and baths:

You can use a bucket of aerated freshwater of equal temperature to the QT/HT for freshwater dips. Freshwater dips will kill parasites and only stress the host fish. The duration depends on the fish species, size and condition, but two minutes is a good rule of thumb for “freshwater dips”, and 20 minutes for “freshwater baths”. Don’t use RO/DI water for freshwater dips or baths. Tap-water has a closer pH and general hardness to saltwater. The chlorine is also medicinal as an oxidant to a certain extent. Do not add medications to freshwater dips or baths as they are not effective and drug toxicity levels differ from that of saltwater.

13) Bare bottom QT/HT:

A QT or HT should never have a substrate as it can harbour parasites in their early life cycle. A bare bottom tank allows you to wipe the inside surfaces daily (if HT). This will dislodge and kill parasites in the tomont, trophont and dinospore stages of the parasite’s life cycle. A diatom filter will remove items as small as 1 micron, and these pests are typically 25-50 microns.

14) A bright flashlight:

There are many fish parasites or cysts that can only be seen with a flashlight as they cast a shadow over the parasite you don’t get with aquarium lighting, while aquarium lighting casts a shadow over the side of the fish, obscuring the parasite or damaged tissue. A flashlight is an invaluable tool for evaluating fish health.

15) A dedicated net:

You can use 75mg/gallon potassium permanganate, iodine, peroxide, bleach or methylene blue as a net disinfectant or sterilizer. Segregate any thermometers, towels, feeding devices, and wash your hands to avoid spreading pathogens to the display tank and other QT/HT tanks.

16) Medications:

Keep medications on hand so they are there when you need them. You don’t want to have to rely on your local aquarium retailer to stock what you need when you need it, especially in the middle of the night on a holiday weekend.

I will briefly touch on the basics here as disease control and treatment warrants a lot more time, beyond the scope of this checklist. The only difference between QT and HT is the amount and variety of medications used. A QT should contain therapeutic levels of prophylactic (preventative) medications, while a hospital tank requires whatever it takes to get the job done. All newly imported fish will have a number of pathogens (diseases) present. If they are dealt with early in their life cycle, they will not cause serious health issues or mortality later on. Here is a brief outline of what I recommend for a QT prophylactic treatment regimen:

– 50 mg/gal chloramphenicol added every second day for three treatments for bacterial infection.
– 250 mg/gal neomycin added every second day for three treatments for bacterial infection.
– 0.20 ppm Coppersafe or Cupramine ionic copper maintained for the duration of the QT for the treatment of Amyloodinium
and external parasites.
– 25 mg/gal quinine sulphate added every second day for three treatments for Cryptocaryon and protozoans.
– 6 mg/100g of food Rifampin fed daily for one week for Tuberculosis.
– 40mg/gal isoniazid added every second day for three treatments for Tuberculosis.
– 2 ppm praziquantel added weekly for two treatments for Flukes and flatworms.
– 1 mg/20g of fish praziquantel – given in food daily for one week for treating intestinal worms.

The above preventative treatment will allow for optimum water quality with minimal impact on nitrifying bacteria and will not cause significant mutation (resistant strains) of pathogens. The QT should receive a 50% weekly water change using display tank water to help with water quality, acclimation and to slowly increase the salinity from 1.018 to 1.025. While it is true that copper can adversely affect a fish’s immune system, the benefit far outweighs the negative aspects, and the QT level of 0.20 ppm is on the low side. Certain “scaleless” fish such as wrasse, gobies and blennies should not be exposed to copper medications; Quinine-based treatments and metronidazole are preferred treatments for these copper-sensitive fish. Quarantine marine fish for a minimum of 21 days to insure parasite life cycles are complete to prevent re-infection.

The following medications are valuable for dips, baths and treatment, but adversely affect water quality, or are better used in target treatment so they are not appropriate for QT:

– Malachite green in a HT or bath for ich & parasites.
– Methylene blue in a bath for parasites and to aid breathing.
– Formalin in a dip, bath or HT for Brooklynella, flukes & ich.
– Nifurpirinol in a bath or HT for fungus, bacterial infection, and parasites.
– Nitrofurazone in a bath or HT for fungus and bacterial infection.
– Erythromycin in HT for bacterial infection and cyanobacteria.
– Metronidazole in HT for internal & external parasites, bacterial infection and cryptocaryon.
– Kanmycin in bath or HT for bacterial infection.
– Gentimycin in bath or HT for bacterial infection.
– Piperazine in food for intestinal worms.
– Oxolinic acid In bath or HT for bacterial infection.
– Oxytetracycline in bath or HT for bacterial infection.

A new, sharp, single edged razor blade can be used to trim away lymphocystis (cotton-like lesions) on the margins of fins.

Oxidizers like the following can be used for treating open wounds by swabbing the area with a Q-Tip:

– Potassium permanganate
– Potassium dichromate
– Lugols iodine
– Hydrogen peroxide
– Merbromin
– Magnesium sulphate


Mr.Wilson Writes on Dipping Corals

First we will look briefly at what we are trying to kill, then focus on a prophylactic regimen of doing so without causing undue stress on a newly arrived acropora. Since stress is the leading cause of RTN (Rapid Tissue Necrosis, i.e. vibrio bacterial infection), we need to make sure we don’t kill the coral with kindness. There is no effective treatment for vibrio so prevention is the key.

The main things we are trying to target are flatworms and red bugs. That was brief, but the treatment isn’t. You need to dip, bath, and QT as there is no all-in-one system. The whole process takes three weeks but you will have peace of mind that your livestock is safe.

Freshwater dips are somewhat effective at eradicating a variety of pests, but they can also cause the coral to slime up, thus inhibiting the effectiveness of medications in dips and baths. Medications should be added to saltwater to assure therapeutic levels and take osmotic pressure changes out of the equation. Certain medications are more toxic in freshwater and directions for marine use often recommend higher doses so they go into solution with all the competing ions of saltwater. In other words, don’t use marine dosages in freshwater. In even simpler terms, don’t use freshwater.

Freshwater dips should be between 10-20 seconds with vigorous swishing around to dislodge the flatworms, essentially kicking them when they are down. Some people use a small powerhead to do this, but I find this to be too hard on acropora tissue, particularly when they are stressed and damaged from shipping. You can blow the paint right off of them if you aren’t careful. If you are experienced, by all means hit them with some flow while you are holding them upside down. A second freshwater dip bucket is handy for a second rinse. Do not use RO/DI water as it is too stressful (osmotic shock). Dechlorinated tap water or remineralized RO/DI water is better. Match the pH, hardness and temperature as best you can.

A more effective dip is 5 mg/gal Lugols Iodine. I would go a little longer (30-60 seconds) and use saltwater rather than freshwater. This could be a second dip/bath after the freshwater dip. You could experiment with other oxidizers like hydrogen peroxide, potassium permanganate, potassium dichromate, and merbromin, but there is something to sticking with proven methods and dosages. Oxidizers seem to be pretty equal as disinfectants. You an use 75 mg/gal potassium permanganate as a spot cure with a cotton swab where eggs and or dead coral tissue is present. This mix should be used for nets and fragging equipment. It needs to be mixed daily as it loses strength as it oxidizes organics it is in contact with. It starts off a vibrant purple then turns brown as it is exhausted. Be careful it will stain and shorten the life of some materials like fish nets (not the stockings, the ones you catch fish with).

Hydrogen peroxide (1-3% as a 5 minute bath) is a useful oxidant for killing parasites and algae. It temporarily raises redox potential and dissolved oxygen as well. At the right dose it’s a miracle cure, but certain SPS are more sensitive than zoanthids and LPS. Here’s a good RC thread on peroxide.

Ed Noga recommends 28 mg/gal levamisole hydrochloride (available as a pig dewormer) for 1.5 hours as a flatworm treatment. Other dewormers like praziquantel (available as Hikari Prazipro) at 1 oz/120 gallons as a 5-7 day treatment, or 75 mg/gal piperazine for 5-7 days are effective. Dylox (Trichlorfon by Bayer), is effective against external worms like gill flukes in fish and flatworms in corals. It is an orthophosphate (insecticide) which can be very toxic so it should be used exclusively in short baths (15-60 mins.).

For the dreaded red bugs, the best treatment appears to be 25 mg/10 gal Interceptor (Milbemycin Oxime). A 25% water change should be done six hours after treatment and carbon, protein skimming, UV, ozone, and ion exchange resins can be resumed. You should repeat this treatment every 5-7 days for three treatments in total. Sterilizing the holding tanks is a good idea. 50 mg free chlorine (sodium hypochlorite) for 2 hrs minimum is sufficient Rinse well and dechlorinate.

Wrasse of the Halichoeres and Pseudocheilinus genera eat flatworms, so they can be added to an acclimation/quarantine system. Commensal (symbiotic) crabs should be reunited with their acropora hosts if they are separated during the dips & poisons. There may be some benefit to cleaner shrimp as parasite pickers as well but I’m not sure how much. In some cases cleaner shrimp become overzealous when grooming dead coral tissue. Larger worms like spirobranchus (xmas tree) fair well in the dip/bath. The same is true of larger crabs and mantis shrimp. The big stuff needs to be removed physically. Killing acro crabs is a common side effect of oxidizer baths.

I don’t know if a short exposure to higher levels of ozone would be a sound practice. I’ll talk Peter into setting up a test tank. We can use one of his six controllers to bring the ORP up to 500 mv and beyond and see if we can find a dynamic equilibrium (magic number of mv ORP) that kills the “bad stuff” and leaves the coral.

There is a rule of thumb for establishing therapeutic levels of medications: use 50% of a lethal dose. In other words, half as much as it takes to kill the fish or coral. Most treatments have safe dosing instructions readily available. The ones that don’t have guidelines will have them after Peter gets his fish room going.


Pegging Corals

Pre-drill your live rock with a quarter inch masonry drillbit. Drill all new corals up through the bottom and afix a short length of acrylic rod or rigid airline. This allows you to place the coral in a stable manner, but also to move it around as the need arises.

For coral pieces 1/4 inch max, 2 inch deep. Buy the rods first and match the rods accordingly. Don’t use a hammer drill as it will shatter the rock. Drill into a solid part so it has a firm base that won’t fall apart. Video on Drilling Live Rock for Pegs

Bigger 1 inch+ holes are good for running PVC pipe with fittings (45s, 90s, tees) for holding heavy reef structures. You can use a diamond hole saw designed for glass drilling to make these big holes. They are remarkably easy to drill.


Mr.Wilson’s General Aquascaping Tips

1) Try to make it asymmetrical. Symmetry makes it look fake.
2) Use the small (orange sized) pieces on the bottom to make a smaller footprint in the sand and create caves.
3) Hide plumbing etc. first, then continue with the rest of the tank.
4) Make sure you orient each rock with the “good side” up, while maintaining the natural strata (the position the rock was formed in) of the rock.
5) Don’t place rocks precariously, for function (balance & stability) and aesthetic reasons.
6) Every rock has a centre of gravity you need to ascertain and respect.
7) Add substrate when the rock work is half done so the rock sits on the glass and not the sand. Otherwise fish and inverts will undermine, and collapse the structure.
8) Make an effort to have a low foreground, medium height mid-ground, and taller background, but don’t make it too contrived or it will look fake.
9) Add more depth by using flat rocks on the back and end walls and through smaller islands or steps in the foreground. You can link these to the mid-ground with bridges, but don’t make it too cute… and no Chinese fisherman statues
10) Remember to leave room for coral to grow at the top of the tank (don’t go too high).
11) Try not to make a straight line of uniform height, break it up with peaks and valleys.
12) Leave some caves for non-photosynthetic corals and cave dwelling fish.
13) Create stable shelves for corals. You can use a pedestal to hold it up.
14) Drill the rock for coral pegs or magnets to hold corals in place.
15) Keep in mind that you want as much area as possible exposed to light. Too many overhangs or steep drop-offs will cause excess shadowing.
16) Use key stones to hold the reef structure together. These can double as bridges. Longer, flat bridge-stones will tie the mid-ground and background together for more stability.
17) Test the stability of the reef as you go. Gently push down on it from above so the rocks lock together naturally.
18) When it’s done, go around the base and middle and remove rocks that aren’t structural. This will open up the reef and create caves without losing structural integrity.
19) Try to picture what kind of corals you want in each location and design around that. Create a gentle sweeping base for mushrooms or colonial polyps on the bottom, and holes in the middle regions to hold euphyllia branches for an overhang effect. Leave large areas for leather corals to fill. SPS corals look best if they are perched with little rock surrounding it.
20) Avoid the straight brick wall style at all costs.
21) Use the biggest rocks before you get stuck with them at the end, when they no longer fit. You can always break them into smaller pieces, but it’s a shame when they traveled so far to get to your tank. You have all the puzzle pieces to complete the landscape, you just don’t have the box with the picture of the finished product on it
22) Diversity in rock shape and size is key. Branches and flat pieces look great, but not if you have too many of them.
23) Most cable ties only last a few years under water, but they can help hold it together as you build and later as corals grow and bond it together. The clear/white cable ties last longer than the black ones.
24) If you use powerheads, build caves to hide them and make sure you are able to remove them every couple of months to service.
25) Make sure that your rock-work doesn’t impede flow from returns or powerheads.
26) Leave access points for closed loop intakes, so you can use a tooth brush to clean them periodically.
27) Incorporate large enough coral perches and nooks to avoid stinging from neighbouring corals.
28) Use large shells or rock rubble at the base so sand sifting fish & inverts can build permanent, stable tunnels. This will stop them from constantly digging.
29) Leave room between the rock-work and glass for cleaning pads and magnets.
30) Use the ugly rocks at the back for stability, but don’t pack it tight, as you need room for fish and water flow.
31) Try to leave a channel across the back at the bottom for a closed loop return or powerhead to eliminate dead spots.
32) Test fit pieces out of the tank before you put them in.
33) Large islands look good, but it’s even better if one of them is somehow linked to another by rock. This helps with eye flow and continuity.
34) Don’t be afraid of breaking pieces to fit. A small hammer is all you need.
35) Use only as much rock as you need. Don’t feel obligated to add more rock just because you have it.
36) If you don’t like the way it looks, start again.
37) Always aquascape while the tank is empty (i.e. no water).
38) Remember to keep looking at the tank from different perspectives as you work, as you need to be sympathetic to all views of the reef. What looks great from one side of the tank may not from another. Even from a sitting or standing position, the look can be affected.
40) Drill out the rock with a diamond hole saw so you can place the rock over a PVC pipe skeleton.
41) Drill holes in rocks to allow effluent ports to have free flow while concealing them.
42) You can use expanding spray foam to hold rock together, but don’t fill void spaces for the sake of doing it, and cover it with aragocrete when it is finished.
43) Bond your reef structure together with waterproof marine grade cement that is protected against sulphide attack. Microsilica as a 10% admix will help make it more sculptable, cure faster, PH balanced, stickier and stringer without shrinkage cracks.

There are three ways of approaching the subject of the presence of hardware in the tank and the tank itself for that matter. Which one you go with is purely a matter of personal preference with no wrong or right answers.

1) Treating the reef structures as artwork that are framed within the aquarium with all walls kept free of significant illumination and free of algae, both coraline and nuisance, as well as other incidental invertebrates such as fan worms. The tank is not in any way concealed as a glass box and maintains a clinical look. I have seen some nice tanks where the lighting is cast only on the reef, leaving the ends darker. LED lighting is directional with limited coverage so this may be a good option if you go with LED. It also limits algae scrubbing maintenance as nuisance algae grows on unpopulated acrylic walls and plumbing while real or faux rock is not conducive for its growth. I would classify Chingchai’s tank as option 1. He has left the plumbing completely visible with the focus on the reef. The viewer’s eye is intended to travel no further than the reef structure, and with his coral diversity and shear numbers do just that.

2) Leaving the plumbing and end panels bare and allowing the reef to partially cover them and let nature take its course and allow algae and misc. inverts to cover them. Depending on the health of your tank, and variety of coralline algae that flourishes, you may end up with green or purple back and end walls. In many cases, the plumbing becomes part of the reef and is only distinguishable to the owner who knows where it is. This approach would include grafting some encrusting corals such as xenia and colonial polyps onto the PVC pipes to influence the outcome. This option is less maintenance than the first one as it limits the amount of walls that need algae removal (scraping).

3) Hide all hints of your captive reef being anything other than magically levitating in your home. This must be achieved without interfering with the function of drains, return lines, closed loop flow in & out, or limiting your ability of altering their function later down the road. This option increase the viewers perception of the tanks size. It becomes harder to delineate where the reef ends and the room begins. Concrete, foam or rock walls provide texture and a calcareous site for additional beneficial organisms to flourish. While it may detract from your four reef structure theme, it gives you the opportunity to add shelves/ledges for corals. You can use a plastic rod to make holes in the cement before it dries for future coral pegging (securing a plastic rod base on corals and inserting the round peg in a round hole where it can be affixed and easily removed for fragging and rearranging). Faux coral walls are less maintenance than option one because to don’t need to wipe algae off of the back or end walls.
Group everything (rock formations/coral/fish) in groups of 3 or 5. Use 7-9 for anthias, chromis or other schooling fish. Your eye always finds patterns with even numbers, detracting from a natural look.


Mr.Wilson Writes About Temperature & Climate Control

First of all the reports that reef tanks thrive at 82°F are absolutely true. Most SPS (small-polyped scleractinian corals) do best at 84-86°F. I aim for 80°F because it is the easiest value to maintain without using any additional resources/energy (heaters & chillers). Once you plug in all of your equipment, the tank will level off to about 79-80°F. It would require the use of one or likely more heaters to maintain 82°F, so I go with the flow and settle with an easily manageable 80°F. If you have a chiller, it should be set to come on at 84°F as basically a fail-safe. Heaters should bet set to come on at 79°F to maintain consistency. If you set your system operating level to 82°F, it leaves a little less room for temperature climbs. A target temp of 80°F leaves room in both directions for error.

A friend of mine was in Indonesia recently and he reports that the maricultured (ocean farmed) SPS are in 90°F water. Coral growth ceases at 76°F, so 77°F is at the bottom margin of their range. 93°F is the top of their range, so 84-86°F (low/high) is somewhere in the middle. 84°F is also the reported level for best growth/health.

I haven’t found “excessive coral spawning” to be a problem. If it was, it’s the kind of “problem” I want.

I believe the data Shimek uses in the article is from 1995. The seas have warmed in the past 15 years.

You need to establish where your temp will tend to drift. Most people have a temp that drifts up during the day while the lights are on. For this reason, it is safer to keep the temp below the optimum 84°F and keep it at 82°F. It’s easy to fix a temp that tends to drift down with a heater, so it’s not necessary to keep it higher than the optimal 84°F.

We aren’t keeping corals from the Atlantic Ocean or Caribbean Sea so the average temperatures from there aren’t accurate for our South Pacific, Australian and Indo-Pacific corals. I’ll look it up when I get the chance, but I doubt the temperatures where our corals come from go below 80°F. This article explains the difference between water and coral temperature.

There are a few things to keep in mind when deciding your optimum temperature. As I mentioned earlier, you don’t want to sit at the margin of the safety zone. Find a spot in the middle where you have room for error minor temperature swings. Temperature drops at the bottom of the safe margin are more dangerous than increases at the top of the margin.

The other issue to take into consideration is your corals need to have all of their needs fulfilled before you raise the temperature (or any parameter for that matter) to the natural optimum level. You can compare it to what a healthy diet for an athlete would be compared to an aquarium designer who chats on a forum all day I certainly have no business consuming the caloric intake of a marathon runner. Corals must have adequate light, carbon source, nutrient levels, major and minor salts and temperature. In the wild, corals will grow best at 84°F, but this isn’t necessarily the experience an aquarist will find in their tank, particularly if they cannot maintain dissolved oxygen rates near saturation levels. Warm water holds less oxygen, so good flow volume and dynamics are vital.

The Shimek article pretty much covers any questions. He claims keeping corals at the low end of tolerance is a common mistake. Calcification ceases at the low end so running chillers to maintain unsafe levels is a poor practice. If/when those chillers fail, you lose stability and increase stress as the water heats up. If your tank naturally runs at 81-82°F with no heater or chiller running, why expend unnecessary resources to lower it if growth and health is better at 84°F?

From Shimek’s article:

“in reality relatively few coral species persist at temperatures much below 24°C (75.2°F)”

“The most rapid growth of most corals is generally around 27°C to 29°C (80.6°F to 84.2°F) (Barnes et al., 1995; Clausen and Roth, 1975; Weber and White 1976; Coles and Jokiel, 1977, 1978; Highsmith, 1979a, b; Highsmith, et al., 1983).”

“the no growth lower limit of zero calcification occurred at 23.7°C (74.7°F) in corals from the Gulf of Mexico and at 25.5°C (77.9°F) in corals from the Caribbean Sea.”

“The most diverse coral reefs are found in a band running from New Guinea and Northern Australia in the west to Palau in the Western Caroline Islands up through the Philippines and Indonesia in the east (Veron, 1986). In this area, prior to the recent period of global warming, the atoll water temperature averaged around 84°F and probably never got as low as 80°F.”

“At 10°C below the optimal temperature, the metabolic rate would be reduced by about 96%, or put another way, it would only be 4% of normal. Under these sorts of conditions most animals die. In fact, most organisms will die if maintained for extended periods under conditions that constrain their metabolic rate to one half of normal. Even metabolic rate reductions to about 75% of optimal may cause significant problems or death (Withers, 1992). A reduction of this magnitude will be caused by keeping an animal with an optimum of about 82°F at a temperature of about 77°F.”

“Both the temperature and salinity of many reef aquaria are kept near or even somewhat below the lower normal survival limit of physiological tolerance for many of the common animals. This results in substantial and unnecessary mortality. In effect, these mini-reef systems keep the animals just healthy enough that they die slowly.” – Dr. Ronald Shimek

We’re talking about a variety of variables that all intertwine. If the question is “What temperature should I keep the coral at?”, then the answer is 84°F. If the question is, “What temperature should I keep my tank at?”, then the answer may differ.

It’s possible that more nuisance algae would grow at a higher temperature. It’s also possible that there is less dissolved oxygen, but I think the difference between 76°F and 84°F is negligible with regard to oxygen saturation. My point about flow rates earlier was simply a warning that if you have a problematic tank with inadequate flow then you don’t have room for higher temps.

Fish are more active at a higher temp. They eat more and grow faster. They would not have a problem at 84°F as this is what they experience in their natural habitat.

The point that Ronald Shimek is making is that it is foolish to keep the temperature at the absolute bottom of the safety zone.

For a large system like Peter’s, I would use an in-line titanium heater run on the main controller. Sump heaters tend to degrade due to salt exposure in the seals and wiring. They also take a bit of a beating during water changes and servicing as they are left on while exposed to air. I use a piece of styrofoam to make a float for the top of the heater so it can float in the sump, keeping the sensitive parts dry (suction cups don’t last long in salt water). The heater(s) should be located in a part of the sump where the water level is constant. The styrofoam floats will allow the heater to follow the water level, should it fluctuate. I would focus my attention on climate control of the ambient room temp with air conditioning or a furnace/boiler, and save aquarium devices in-line or in the sump for fine tuning.

While I would never talk anyone out of a fail-safe device, you have to remember that everything you plumb into your system could potentially leak, and everything you plug in could potentially cause stray current or shock/fire hazard. I don’t use chillers as a general rule. It’s part of the K.I.S.S. (keep it simple stupid) or “less is more” approach.

The factors that influence system temperature are as follows…

1) Ambient room temperature: North American homes are warm in the winter and cool in the summer, thanks to our desire for convenience and comfort and with a little help from huge utility bills As a matter of fact, many homes are warmer in the winter than they are in the summer, and cooler in the summer than in the winter. Typical ambient room temperature is somewhere around 72°F (for the record, we use metric in Canada).

Working with 72°F, we can assume that still water will reach equilibrium with that temperature. Once you start moving the water it has more contact with the surface where the temperature reaches equilibrium. A cooling effect starts when surface water evaporates and takes with it heat. Evaporative cooling is a very important process that we will discuss later.

2) Aquarium location: This factor is directly related to the ambient room temperature covered above. An aquarium located in a basement, or with a sump in the basement or garage will run cooler than an aquarium in an upper floor of a house. Even the position of the tank with relation to the floor makes a difference. While I operated a tropical fish wholesale warehouse, I found that the three levels of tanks showed different temperatures. The freshwater tanks where not on an open system, just air-driven sponge filters. I heated the warehouse to 80°F, but the bottom tanks 1′ off of the ground were 74°F, the middle row 3′ off of the ground were 76°F, and the top row 5′ off of the ground were 78°F. Peter’s radiant floor heating will eliminate this heat gradient issue. Placing the sump directly on a concrete floor will offer cooling.

3) System volume: Having a large sump is a cheap and easy way to improve thermal dynamics if you have the space. The extra system volume will also improve water quality, as the saying goes, “The only solution to pollution is dilution”. The best solution is actually filtration, rather than sweeping the problem under the rug, but it doesn’t rhyme so I doubt it will ever catch on.

Saltwater has greater density than freshwater, so it holds its temperature longer. Large tanks (over 200 gallons) are particularly stable with little or no fluctuation caused by day/night ambient room temperature shifts. In other words, the room may be cooler at night, but the tank will stabilize at a compromise temp somewhere between the day and night temp. The large thermal mass of a big tank makes quick temperature changes up or down more difficult, but nature doesn’t like change, so overall the thermal mass is a good thing for stability. Remember that bleaching incidents on natural coral reefs has been noted after only 2°F temperature increases. This doesn’t mean a 2°F increase in temperature will bleach (expelling symbiotic algae/zooxanthellae) or kill corals, but it does underscore the necessity for stability.

4) Heat transfer: Every electrical device, including chillers add heat to aquariums. Add a few degrees for pumps, a few more for UV sterilizers and a lot more for lighting and your cooler than room temp tank is suddenly 10°F hotter. Some of this heat is unavoidable, but most of it can be at least minimized. Directing a 12 inch circulation fan perpendicular toward the display or sump surface will drop the temp 5-9°F. The evaporative cooling effect will tax your top-off system a little more so make sure you can keep up with the demand. A second fan can be used to blow across the surface of the water, pushing radiant heat from the light away from the water. Raising or lowering the lights will also influence heat transfer.

Venting the cabinet or filter room is an often overlooked detail of climate control. Some pumps don’t employ cooling fans and subsequently run at very high temps (130-140°F). This is not a problem if the heat is allowed to vent away from the system, rather than trapping it and raising the ambient temp and surface water temp. Chillers are an important device to vent as the heat exchanger will dump that heat right back into your system so it works against itself.

5) Water movement: As mentioned in the previous points, good water movement will increase the amount of water exposed to the surface for thermal and gas exchange. A good system of flow dynamics assures that water is moved from the bottom where it is cooler and lower in dissolved oxygen to the surface where it can be oxygenated and heat can vent. Using a glass top will raise the temperature about 5°F. While this is rarely desirable, it’s a good practice if there is an extended power outage and your back-up power is limited. I assume Peter has a natural gas generator and UPS/deep charge marine battery backup. Certain filtration devices (gas reactor, wet/dry filter, shallow ATS etc.) work as evaporative coolers or cooling towers. In general, these evaporative efforts are directly connected to improved gas exchange as well.

6) Air quality: Fresh, dry air will be cooler than stale humid air and gas exchange is more efficient. Peter’s HRV unit is more than enough to handle this issue. It also vents equipment to deal with heat transfer.

You should have a bypass line on all of the equipment such as the chiller so it can be taken offline for service without affecting the operation of the aquarium. There should also be a true union shut off valve on each bulkhead of the display tank. This way you can fill and run the tank independent of the plumbing and filtration devices and if your plumbing springs a leak it can be repaired without draining the tank or capping the internal plumbing.

There’s a handy chart on this site that illustrates the relation of salinity and temperature to dissolved oxygen potential.

For Peter’s tank I recommend he pick up two 1000 watt titanium probe heaters and plug them into a controller. Make sure the module/power bar can handle the 20 amps that it will draw. Having each heater run on a separate controller will resolve this issue and act as a failsafe. If the controller jams in the on position the tank will only go up 5°F instead of 10. If the controller jams in the off position, the other heater is still on the job.

We discussed heaters earlier in the thread. The experts agree that the ideal temperature is 86°F. The room temp may drop at night even with your climate control system. The most important issue is stability. In my experience the tank will run about 5°F warmer than the room. Evaporative cooling will drive the temp below room temp and LED or well vented MHL lighting has little affect on water temp. Your pumps are all external so they won’t transfer as much heat as submersibles. Your UV unit will add a bit. The trickle/wet dry filter will cool the water through evaporation and contact with air.

Where you see a lot of overheating issues is with a tank under 200 gallons with MHL lighting crammed into a tight canopy, poor cabinet venting, inefficient pumps, powerheads, and high ambient room temp.

Cold air drops so your basement will have a cool ambient room temp year round. Your remote sump and equipment will keep the tank cool. I think you said your live rock vats were about 78°F.

The problem with magic numbers is they aren’t magic for everyone. Peter has a high tech climate control system and a budget to keep it where he wants it. There are numerous fail safes and the high water volume and acrylic tank tank construction offers yet more stability. Fear of a temperature drop during a power outage or a high temp spike during a heat wave are not factored in when establishing target temp. If you have all of your ducks in a row, then a magic number of 82-84°F fits the bill (no pun intended).

If you feel you are at risk of power outage, extreme weather (hot or cold), or equipment malfunction, then you should aim lower, closer to the middle of the temperature range (79-80°F).

In most homes, it gets cooler at night. This can drop the system water a few degrees, especially since lighting and in some cases pumps are off at night and cooling fans are often left on. Most fish and corals are from areas with stable temperatures. The temperature swing is more injurious than the temperature value itself. For this reason, it makes more sense to keep the heater at 80°F rather than 79°F or lower so nightly drops are compensated for.

You can use a chiller to keep the temperature from rising over 80°F, but that represents a $1000 – $1500 equipment cost and elevated operational costs. It also increase the possibility of leaks and equipment failure.

I don’t know the actual numbers, but the amount of dissolved oxygen in 79°F water versus 82°F water isn’t a huge difference. Keeping the resting temperature lower will add extra minutes of air, rather than hours.

I posted an article by Dana Riddle earlier where he compares water temperatures to actual coral temps in aquaria. He uses a directional infrared thermometer to test the temperature of the coral. Some lighting systems emit radiant heat that reaches the corals, making them warmer than the surrounding water. The sun also generates radiant heat, obviously, so this heat transfer is not unique to our aquariums.


Mr.Wilson Writes on Mechanical Filtration

First of all, I’m in the minority as a proponent of mechanical filtration. Up until the early 1990s it was a primary function of marine aquarium filtration systems. Then along came a few authors like Julian Sprung with the great idea that much of the junk we were collecting was in fact food for corals in our “nutrient starved tanks”. As the hobby moved to more challenging hard corals (LPS & SPS) the demand for nutrient-poor water was increased, but for some reason the mechanical filter never came back into fashion. It just isn’t a sexy high tech device you can show off to your friends. The value of detritus as a viable food source for coral was a little weak anyway, so I’m all for the removal of it before it enters the nitrogen and phosphate cycles (nutrient cycle).

The advent of wave and surge devices coupled with engineered flow dynamics at greater volumes, meant that detritus stayed suspended for longer in modern systems. This resulted in a “snow globe effect”, whereby detritus floated through the system almost indefinitely. Sure the protein skimmer captured some of it but in the absence of a filter sock, foam pad, polyester floss, pleated cartridge filter, or settling container you are relying on corals to consume detritus, when they are not detrivores.

Now more than ever we need to use mechanical filtration. It does not rob corals of nutrients and it does not make the water “too clean”. Mechanical filters increase water clarity, removing the collective yellowing effect of pigmented organics. This increase in clarity improves light penetration and photosynthesis. Pleated cartridge filters such as the ones Peter is using are typically rated at 25 microns, but with clogging they can remove particles down to one micron. This means that certain parasites like ich will be physically removed.

There is such thing as too much mechanical filtration however. You have to leave some “food” for corals. For this reason I would consider running a filter cartridge in only one of your two mechanical filters at a time. Every week you can swap canisters and cartridges. You do have a big tank, so two filters is probably right-sized for your application. Alternatively, you can use the cartridge unit as a media filter and fill it with carbon, phosphate remover, or carbon source pellets etc. Some pleated cartridges have a hollow core with a perforated nylon tube in the center for holding chemical filter media. Another caveat of mechanical filtration as it is only as effective as the user. Once the detritus is trapped in the cartridge it should be removed within a week, preferably sooner. If you don’t remove the cartridge for cleaning the detritus breaks down and dissolves and enters the nitrogen cycle as bacteria starts to consume it. Make sure the canister is easy to reach with shut-off/bypass valves and clearance to exchange cartridges. Order a few extra cartridges so you can periodically bleach them and keep clean ones in the on-deck circle for cleaning time.


Mr.Wilson Writes on Cryptic Zones

For those who aren’t familiar with it, cryptic, twilight, or benthic zones are areas in a reef where little or no light penetrates due to shadowing from corals and rock and shear depth as tiny particles in the water refract light. These areas are also low flow for more or less the same reasons.

The invertebrates that grow in cryptic zones have adapted to be opportunistic feeders, dining on excess nutrients such as nitrogen & phosphate, heavy metals, bacteria, free-floating algae and other junk from the illuminated reef above. Corals growing on the sunny side of the reef have adapted to utilize algae within their tissue to derive energy from carbohydrates (sugars) that their symbiotic algae partners (zooxanthellae) produce through photosynthesis. Cryptic inverts have adapted in a non-photosynthetic environment. To make up for the lack of free energy from the sun and algae, cryptic inverts have taken advantage of what they have a lot of, and that’s a steady rain of garbage (detritus & nutrients) from the reef above.

Cryptic zones in aquariums don’t need to be highly engineered as they occur naturally as a matter of course. Anywhere there is a dark area where algae won’t grow, miraculously small cryptic inverts will appear like the guys selling $5.00 water at music festivals. These inverts include sponges, sea squirts (tunicates), fan/feather duster worms, serpulid/fire worms (look like sea earthworms and often sting like a cactus), bivalves (clams, scallops etc.), barnacles, and plankton. The areas you will find them in your tank are overflow boxes, sumps, in the substrate, and on the undersides of rock and coral in the display tank.

There is a saying that “nature doesn’t like empty spaces”. Wherever there is an excess of food, or available home, an opportunistic organism will find it and set up shop. When you feed your tank a good portion of that food goes right over the overflow box unless you have a system to shut down the pumps or a feeding station of some sort. Aiptasia and majano anemones are photosynthetic, but they are also active filter feeders and collect passing food with their handy tentacles so overflow boxes are a perfect environment for them. Filter feeders draw in water through their tissue and polish it by removing the nutrients, heavy metals, and organic carbon (TOC). The removal of these food items not only helps with he chemical composition of the water, it also improves water clarity which helps light penetrate as the yellow pigmented organics are removed.

We can replicate the natural balance of organisms that nature uses by providing more homes for cryptic inverts. In nature, the cryptic zone is exponentially larger than the illuminated reef. By spacing our live rock and adding structures to overflow boxes and sumps, we can make up for the chief growth limiting factor (real estate).

The key to cryptic filtration is location… location… location. I build eggcrate structures and place them in sumps below the refugium as a “Duplex System” for better use of space. The duplex term refers to the upper illuminated refugium and lower basement apartment for our cryptic friends. The network of eggcrate panels allow water to passively move through while providing a 360 degree surface for cryptic inverts to attach. I call these natural/biological filters “benthic zones” due to the replication of a substrate, rather than an underside of a reef rock like the cryptic zones that Steve Tyree has created. Tyree’s systems are comprised of unique rock formations that allows for more shadowed areas. You can read more on his systems here and here and you can read more about similar benthic systems here.

Cryptic inverts get into your tank as hitchhikers on the dark side of live rock and corals. Some sponges and sea squirts (looks like a sponge but with two vents/mouths) are very colourful and can be bought as specific pieces. While the actual effectiveness of cryptic zones on water quality is hard to measure and separate from other filtration efforts, at the very least they offer a fascinating look at a different level of the natural reef ecosystem.

In theory and in specific scientific studies, sponges and other water polishing inverts have proven to be beneficial to water quality management, but feedback on how much impact they actually make on a reef tank are slow to come. Part of this issue is due to a lack of hype typically surrounding commercial products catering to the niche market. In the case of protein skimmers, they have been proven to only remove 80% of available proteins and 20% of available TOC (total available carbon). It has also been proven that there is little difference between the results from high end skimmers and cheaper models of the same size rating. Despite this knowledge, protein skimmers are highly credited and revered for success. The same is true of LED lighting. Aquarium shows are wall to wall LED manufacturers now but the truth of that matter is mass produced LED light fixtures pale in comparison to MHL, no pun intended. There is a strong positive feedback for these systems with very few unsatisfied users, so that is encouraging.

I think we are getting honest, unbiased feedback on cryptic and benthic zone filtration and it’s something we aren’t entirely used to. We are accustomed to measuring the merits of a technology or methodology by reviewing numerous articles and threads expounding their virtues. You just have to filter out the hype and commercial biased. The only criticism I have heard is in regard to detritus build-up if the area is inaccessible but in my opinion this is due to poor design/access for cleaning and skipping important details such as pre-filtration (mechanical filtration) and omitting larger voracious critters like starfish, urchins, and crabs to keep the zone clean. We need to reflect on nature to focus on ways to replicate its success. In nature there are micro (small) as well as macro (larger) invertebrate janitors in the cryptic/benthic zone. A benthic zone sump is a perfect area to throw unwanted reef bandits like parasitic coral picker crabs, fish or coral eating starfish, and coralline algae eating urchins etc. Sea cucumbers are another good addition, as well as non-photosynthetic bivalves such as flame scallops that polish the water by removing diatoms, cyanobacteria spores, phytoplankton, ammonia, phosphate and nitrogen.

A rich biodiversity in your system is the key to striking a natural balance. We can tip the scale a bit to our favour by providing more real estate for cryptic invertebrates, thus eliminating the growth limiting factor. Cryptic zones are not only a method of removing excess nutrients, but a way of providing nourishment for fish and corals in the display tank as it is a perfect plankton farm/nursery (plankton like slow flow and darkness).

Some critics claim that cryptic zones are contributing to the bio load and are nutrient producers not consumers. The food these inverts are consuming is not being added (imported) for them, and they are consumers not producers like algae. They are just cleaning up (assimilating and dissimulating) a nutrient and organic load that already exists as a surplus. The members of the cryptic community are diverse enough to assimilate organics without leaving residual nitrate. The chief denizens of the cryptic zone are detrivorous (detritus/debris eaters) worms and sponges & sea squirts that directly consume nitrogen (ammonia, nitrite & nitrate), as well as bacteria, free floating algae, and iron.

Whether you want it or not, you have cryptic zones and subsequent filtration. The question is how to make the most of it.


Mr.Wilson Writes on Coral Light Requirements

Selecting intensity (wattage) is a matter of water depth and the type of corals you want to keep. If you plan on having SPS, than you need to be at the high end of the scale. The rule of thumb for selecting intensity with a mixed reef is:

150/175 watts for tanks up to 24 inches in depth
250 watts for tanks up to 30 inches in depth
400 watts for tanks up to 48 inches in depth
1000 watts for anything deeper than 48 inches

These numbers are recommended with regard to keeping a mixed reef with high and low light corals kept at respective depths. The sun travels 94 million miles to reach the surface of the ocean. From there, light is refracted and filtered out by salts and other particles on the water, removing the red and yellow light that the human recognizes as bright. The remaining blue light is what makes it to the deeper depths.

Considering the distance the sun travels, it decreases in intensity over miles, not inches, so you get the same amount of sunlight on your bald spot as you do on your feet. Artificial lighting is another story. You lose 1/2 of the intensity with every 12 inches it travels. This means that mounting height makes a significant difference. So 250 watts mounted 18 inches over the tank is equal to 150 watts mounted about 8 inches over the tank. On top of this, we still have the light we lose as it is filtered out by our turbid yellow aquarium water.

If you can handle the heat and electrical bills, it’s better to go with higher wattage and raise the fixture or dim it to accommodate the corals’ requirements.

LED is the way to go if you can get a DIY or custom fixture. I haven’t heard of any mass produced fixtures that can compete with metal halide lamps for shimmer, PAR or coverage. Energy saving is about 50% but that isn’t much of an inducement with a $200,000.00 tank.

There are no known negative aspects to a lack of UV, or conversely benefits to having it, but in my unpopular opinion natural conditions should be replicated and UV does readily exist on natural reefs. Corals develop UV protection (mycosporine-like amino acids/MAA’s) as sun block from the harmful UV rays of the sun. Reef fish have these same MAA’s in their mucous. These were originally believed to be pigmented but are now known to be colourless. The zooxanthellae (symbiotic algae) within the coral’s tissue are a light brown or drab green colour and do not require UV to our collective knowledge. This article and the series by Dana Riddle covers the subject of lighting and coral colouration.

PAR is the biggest single lighting parameter you need to monitor. It will indicate if your bulbs are old and if they are adequate in the first place. PAR is basically the quality and intensity of light that is required for photosynthesis. LUX is the intensity reading that includes the higher nanometer (nm) light that is easily recognized by the human eye as being “bright”. These readings are good for testing bulb life but do not indicate the hidden PAR generated by the light.

The other consideration is coverage, as LED tends to cover a smaller spotlight area compared to MHL or natural sunlight. Home & office use LED lamps are starting to use 7 watt multichip LED clusters, and there are even 100 watt LEDs used in the aquarium trade now.

There are two ways of looking at the lighting issue. One way is to find out what corals appear to require for growth, health and colouration, then create those conditions with the technology available to us. The second approach is to match the lighting conditions of natural reefs and assume that nature got the formula and balance right and we can’t improve upon it. It’s a matter of personal choice just like GMO’s (genetically modified organisms) or organic foods.


Mr.Wilson Writes on a Deep Sand Bed in the Overflow

You can always fill the bottom 2/3 of your overflow boxes with sand. I’m assuming you are using an 80-90% siphon drain with a 10-20% durso/aspirated drain to pick up the slack. It may not be big enough for your system, but it’s a good use of dead space. I use perforated PVC tubes imbedded in the sand to increase the barrier layer (more sand/water interface/surface area) and to allow access for carbon source dosing, solid vodka media, and sulphur media replacement. A heater or air line could also be placed in the tubes for passive flow around the sand. If the water overflows aggressively, add course sand to the top inch to avoid and storms, but it shouldn’t be an issue if the box is designed correctly.

The sand never needs to be changed out. In the old days we changed it annually because calcareous media like coral sand is a silicate and phosphate sink, constantly binding and releasing nutrients back into your tank. With modern phosphate media filters and other devices that is no longer a concern.

It’s a bacterial and to a lesser extent, chemical process taking place in the DSB. This is an area where hobbyists can run wild with experiments using carbon sources, sulfur beads, sand mixes and yes, Magic Mud. Studies have shown that nitrifying and denitrifying bacteria populate detritus on the sand forming a slime coat or biofilm, rather than simply growing on the sand grain itself. This is an area that may give Magic Mud credit. The slight turbulence of an overflow box would turn the already partially buoyant magic mud into a fluidized bed. This would give you a much larger barrier layer between the media (in our case mud) and the nutrient rich water.

You can also create a passive flow through the sand or mud by installing a heat source below the overflow box. As the heat rises up through the box it takes with it a very gentle current of water. This would be just enough to expose more water to the media without turning the bed into an aerobic zone. Denitrifying bacteria colonizes aerobic (oxygen-rich) as well as anaerobic (oxygen-poor) zones. The DSB should offer a variety of conditions for different species of denitrifying bacteria.

If you are following any of the carbon dosing threads, I’m sure you have read this one. In the good old days we dosed lactose, ethanol (vodka), or a glucose solution daily in a slow flow media reactor. These days the common practice is to dump much higher doses directly into the system. Feeding a carbon source in smaller, controlled doses, directly to the bacterial bed in a DSB rather makes more sense to me still. The argument for shotgun dosing the whole tank is that microbes living on coral tissue consume nutrients (phosphate & nitrate) at the source on a collectively high level.

It would be easy to isolate which, DSB or microbes on coral tissue, is more active with denitrifiers (nitrate reducing bacteria) by running a few test tanks, but no one has expressed an interest in the matter. Personally, my money is on the DSB and the popularity of bulk dosing is a product of simplicity. Vitamin C is photo degradable and hydrophobic (skims out easily) so most of the ascorbic acid added is quickly removed anyway. This would not be the case in a DSB overflow box where there is no light to degrade it and its safe from your protein skimmer. Just drop a much smaller dose into a perforated PVC or Nylon “feeder tube” in the overflow DSB and you get direct feeding without waste or residual chemicals.

The feeder tubes themselves are simply a perforated pipe with an end cap at the bottom to keep sand out. They are completely independent of the drain system which consists of a siphon and gravity (Durso) drain drawing water from the top 6″ of the overflow box. Our overflows will have one 2″ dia. tube in each. Time will tell how it works out. The siphon line runs down through the bottom of the tank and does not hook over the top of the tank like a traditional siphon drain.

The 1.5″ siphon drain is controlled by a ball valve to draw out 90% of the water we need to drain. The remaining 10% is made up with a 2″ gravity drain. The siphon can fall behind in demand and the 2″ gravity drain will make up the difference. This way slight variations in siphon speed will not affect the draining process. If we relied 100% on the siphon drain it may over-siphon and lose prime, causing a toilet flush noise as it goes in and out of siphon. By under utilizing the siphon and allowing the water in the overflow box to climb a few inches to the Durso gravity drain, we can only have variation in the Durso’s rate. If the siphon drains clog, the 2″ Durso’s are more than enough to drain our demand in the case of an emergency, even if they don’t kick into siphon themselves. Remember, a siphon can move exponentially more water than a gravity (aspirated) drain. A siphon uses surface tension to actively pull water down the pipe with no space occupied by air.

Denitrifying bacteria can be anaerobic or aerobic. The serious business gets done in the first 1″ of sand, not necessarily due to oxygen saturation, but more because of water exposure/turnover. Denitrifiers also convert nitrate back into nitrite in a process called kickback, by the way. Each layer of sand consumes oxygen so the deeper you go the more anaerobic it gets. The key is to find the right amount of oxygen or lack thereof without losing water turnover.

We are aiming for hypoxic (low oxygen level), not anoxic (very low oxygen level) for our overflow deep sand bed (ODSB). Our ODSB will be about 24″ deep so we want to assure that we are using more than the first few inches for denitrification.

Canister style denitrifying filters use a slow drip feed pump and a second recirculation pump to assure water moves freely throughout the bioballs, carbon media, or sulfur beads and calcium carbonate media. Our ODSB is a passive system that hopefully bridges the gap between the efficacy of a recirculating canister and a static bucket of sand with water slowly running across the surface (Calfo bucket).

The tube we are using will only allow a slow exchange of water. There are no pipes directing flow down it and no water being actively pulled up it. We will use a dissolved oxygen (DO) probe to keep track of what the DO is in the various levels of the tube and surrounding sand. Obviously the farther you travel from the tube, the lower the dissolved oxygen. This may not be entirely true if we actively pull water out of the tube as water will fill the void by moving down through the sand from the top (like an under gravel filter for those who are old enough to remember them).

We can also take samples from within the tube to see if we have a lower nitrate or phosphate level at deeper depths in the ODSB. If we can prove that the sand bed is working, then the next step is to prove that it can work better. As long as we can maintain zero nitrates within the ODSB we will continue to push it harder by feeding more water through it. Once we see nitrate in the ODSB we can back off our water feed/exchange rate as we will know what the denitrification limitations are.

The feed tube can be capped with the DO probe left inside to test “normal” DO levels. The tube may not add any oxygen on its own, without a heat source to lift water or a dosing pump drawing water out from the bottom. Water takes the path of least resistance so it will naturally be drawn to the siphon & gravity Durso drains.

The other issue we hope to explore is the addition of a carbon source. Most people who add a carbon source (vodka, lactose, glucose, ascorbic acid etc.) do so in large volumes because they are not directly feeding a denitrifying filter. While there is some value in feeding carbon to microbes on the surface of coral tissue, most of the demand for carbon is within a DSB or denitrifying filter of some sort. We hope to eliminate nuisance algae and protein skimming issues by directly feeding the denitrifiers with our feeding tubes.


Mr.Wilson Writes on Cleaning Acrylic Tanks

I would go with a Mag-Float 1000 Professional. You should add a fleecy pad for acrylic tanks, or better still buy chemical-free Mr. Clean Quick Eraser pads and cut them in half to make them thin enough to be held with the magnet. The Quick Erasers polish the acrylic while removing stubborn algae.

I also use a microfibre cloth on the outside of the magnet where it touches the acrylic. Sew it into a pillowcase shape to fit over the magnet so it doesn’t slide off. A soft sock works too. Keep the outer cloth clean and free of sharp debris that can scratch the acrylic. I wash the outside of the tank first with water to remove salt residue that can scratch.

Check the magnet regularly for sand and snails etc. Keep it out of the water to avoid sharp tube worm growth and to protect the magnets. The magnet is extremely strong so be very careful using it. Put the wet end in the tank against the acrylic, then slowly slide the outer magnet up to it as you move it across the surface of the viewing panel.

Angle your lighting inward so the viewing panels are not directly illuminated. This will cut back on nuisance algae growth and avoid casting shadows on the fish and corals.

The Kent scrapers with the red plastic blade for acrylic are good. Credit cards also work.

If and when you get an external scratch you can have the area buffed with jewelers ruby paste and a cloth buffing wheel on a hand drill. The hand polishing kits are for micro-scratches. You can address interior scratches on the wet side with wet sand paper on the magnet starting at 100 and going up to 2000 grit. If you are diligent this will not be an issue.


Mr.Wilson Writes on Fish for the Reef Tank

Diamond sleeper gobies (Valenciennea paullaris) are very nice and should always be kept in pairs. The male is usually smaller with a taller dorsal fin. If you want to add more of them, then go with some diversity and add my favourite of the Valenciennea genus, V. Wardi, Tiger Sleeper Goby.

Tiger Sleeper gobies stay close to the substrate with their mouths of sand so they don’t make a mess like V. strigosus, Goldhead Sleeper Goby. They are also more hardy than the other members of the genus. I used to keep them with their commensal (symbiotic buddy) pistol (Alpheus sp.) shrimp, until I found out that they eat cleaner shrimp and the occasional fish. The clicking noise also drives me crazy as they sound identical to the more fearsome mantis shrimp. It’s a cool display with the two gobies keeping watch and the blind shrimp maintaining the cave they all share. The shrimp uses a tentacle to constantly read the signals the “look-out” gobies give. Speaking of which, signal gobies (Signigobius biocellatus) are another favourite of mine that have a three-way relationship with a shrimp. And the shy but resplendent Antenna gobies (Stonogobiops sp.) and my favourite invisible fish the cave goby. The nicest goby, although not a sand sifter, I have had came in by fluke as a “waif” from The Philippines, the Helfrichi Fire Goby.

The experts all agree that deep sand beds should be left alone, so sleeper gobies and any other sand sifting fish and invertebrates should be limited to tanks with a maximum sand depth of 2″. A remote sand bed can be easily added with a 55 gallon drum on a flow-through somewhere in your system that is free of detritus.

It’s the relationship between the fish and how they fit together as a group that is interesting, more than just gaudy colours. You want fish to fill all zones of the tank with gobies and blennies on the bottom, schooling fish in the middle near the top to draw out the timid fish, and some bigger fish in open areas.

I have seen cases where a large reef tank with 40 fish can appear devoid of fish due to their shyness. Once a school of anthias or chromis is added they know it is safe from predators and they all crawl out of the woodwork. We call these schools of fish “dither fish”.

Some Swallowtail angels (Genacanthus sp.) eat anthias feces. They hang out below large schools and wait for the anthias to “make it rain”

Tile gobies and certain blennies mimic anthias so they can blend in with the crowd for safety when traveling. Normally I wouldn’t recommend tile gobies because they don’t adapt well to reef tanks, but they are fine with big tanks and look to scale (they put small tanks out of scale with their rapid swimming patterns and larger size 6″). The flashing tile goby is amazing as seen in this not-so-great video. Purple tile gobies are even more colourful, but they stick to one vibrant colour.

Garden eels are another one that may work in a big tank like Peter’s, but they need deep sand. You may be able to design a segregated sand area with deeper sand.


Mr.Wilson Writes on Water Chemistry

Your stocking level will determine your need to replace/supplement more exotic elements as they are utilized by corals and biological process. These include but are not limited to strontium, iodine, manganese, boron etc. Keep in mind these “trace element” are also “heavy metals”, so you will be feeding nuisance algae and poisoning corals if levels are allowed to elevate. These elements enter the aquarium through water changes to a slight extent, and are constantly being added with feedings (nutrient import). These elements are constantly leaving the tank through protein skimming, water changes, and algae farming (nutrient export).

The water chemistry issue needs to be fine tuned according to what your goals are and how you want to get there. For example, your calcium reactor, if sized right may be able to handle all of your needs if you don’t go too heavy into SPS; however, I predict that you will be tipping the scales so a dosing system or Nilsen reactor (kalkwasser reactor) will be in order. Some people use very complex dosing protocols to replace what is missing and remove what is in excess, while others are able to strike a balance with one catch all product like Tropic Marin Bio Calcium.

The key to maintaining optimum water chemistry (we’re not talking about water quality here) is to monitor each parameter carefully and replace the deficit accordingly. There is a complex reaction when you add any chemicals to the tank so you need to strike a balance. For example, adding too much of any one element may cause a snow storm in the tank as chemicals fall out of solution, leaving you with a snow globe. pH is also affected by these additives and can drift up or down if you aren’t careful. Where most aquarists get into trouble is with shotgun dosing and knee jerk remedies to correct their mistakes.

To oversimplify it, saltwater is made up of all kinds of stuff. Corals use all of those stuffs as building blocks for their reef building skeletons. What is a reef made of? Sugar, of course. Through photosynthesis, the energy of the sun and CO2 in the water is used by the symbiotic algae that lives within the coral tissue to produce carbohydrates (sugar) that bind with calcium in the water to form … you guessed it, calcium carbonate. Instant reef.

Now I know what you’re thinking, “I thought you were going to over-simplify it, Shawn”. Well, here’s the easy part: you keep track of the stuff that gets smaller like calcium, and add as much as it takes to get back to the magic number. We are fortunate enough to know what natural sea water (NSW) is comprised of so we know the target numbers to shoot for … and no, you cannot improve on Mother Nature’s evolution so stick with NSW numbers.

Here’s where you could potentially screw up:

1) You use the instructions on the label to dose for x number of gallons. You are dosing for your bioload and consumption, not for bulk system water.
2) You don’t have fail-safes in place and accidentally overdose.
3) Your test kit lies to you and you think you are too low with one parameter when in fact you are too high and getting worse.
4) Missing the balance between lighting, water quality, CO2, salts, and elements.
5) You start a roller coaster effect by adding too much of one element then overcompensate with another.
6) Bad chemicals that have either taken on moisture, or fallen out of solution with age, or have become more concentrated due to evaporation.
7) Listening to bad advice or misinterpreting good advice.
8) Following the misconception that you need to put pressure on your corals to grow by continually adding more chemicals.
9) Not allowing corals to adapt to the elevated heavy metal levels of our captive reefs.
10) Misc. human error and calamity.

One point I should stress is that it’s difficult to do harm to a coral by underdosing elements, while overdosing is a very common cause of coral damage and mortality.

These chemicals interact strongly with each other. Adding too much of one can cause another to fall out of solution (turn from liquid to solid or at least bind with another chemical). Most of these elements will also impact pH either up or down, so keep an eye on your pH meter to establish if you are adding too much too fast. There is such thing as too much of a good thing in this case.

Think of corals as being similar to our bodies. We utilize calcium and many of the same building blocks to build our skeletons. A deficit will not quickly kill a coral, while a surplus will do harm. You just need to go slow and keep the trace elements and salts at NSW levels. Too much of anything becomes poison. Too little will only retard growth or cause the colours to fade.

In the end, all of the testing equipment in the world won’t equal the signals the corals are giving you. Open (feeding) polyps and natural bright colours are your natural meter.

Here’s an article by Randy Holmes Farley discussing his calcium and alkalinity supplementing system.

Most of the ionically balanced supplements are based on his formula or earlier ones (1992) by Alf Jacob Nilsen published in FAMA (Fish and Marine Aquarium magazine). Jack Kent from Kent Marine based his entire business on the reef recipes created by Nilsen.

The important thing to keep in mind with regard to replenishing depleted elements is water changes only address the volume you are discarding. In other words, if you have a 100 gallon tank and do a 20% water change, the 20 gallons you replace will have the correct NSW (natural salt water) levels, assuming your salt is worth its … how does the saying go? … salt. The other 80% (80 gallons) will remain at the depleted level. Of course once it mixes, you get an average that is lower than NSW with respect to the “good stuff” that corals need, and higher in “bad stuff” that accumulates and becomes toxic to corals.

Another common misconception is that elements are depleted only through coral growth. Reef building corals, particularly fast growing SPS, do in fact consume a fair amount of calcium, carbonates (KH), and magnesium etc., but you also lose a great deal of these through the growth of coralline algae, hard tube worms, and down the drain with what your skimmer collects. These two studies show that there is a substantial amount of calcium removed through protein skimming. In some cases the calcium is in the “raw form” from a calcium reactor (not yet fully dissolved into the water). In other cases the calcium is bound to particles (POC/particulate organic carbon), and in other instances the calcium is sources from the outer shell of plankton that the skimmer has trapped. See table two here and this article here.

The interaction of chemicals in the water causes some additives to fall out of solution and bind with other chemicals you are adding or are already present in the water. For example, when you add a calcium supplement such as calcium hydroxide or calcium chloride, the calcium ion may partner up with phosphate to form calcium phosphate and precipitate out of the water column. While you lose a small amount of calcium through this interaction, on the plus side you rid yourself of some phosphate that would otherwise feed nuisance algae.

As in the ocean, the calcium-based (calcareous) rock and substrate in your tank will slowly dissolve and add the essential elements your corals need for growth, completing the cycle. The nitrifying and denitrifying bacteria in your rock and substrate release a localized acidity which dissolves some calcareous media. While this is only a small portion of what your tank consumes, it’s a natural supply of recycled elements. If you were to grind up and analyze the composition of dead coral, sand, and reef rock, you would find the exact elements that corals require in the proper proportions. Like us, corals are what they eat. A calcium reactor does this exact process in an isolated container where the tank pH will not be affected (lowered). Calcium reactors use acid (carbonic acid/CO2) to dissolve calcareous gravel by lowering the pH (acidic environment). If you can iron out the kinks with cheaper calcium reactors to assure a steady drip of CO2 and processed water, they are pretty much “set it and forget it”. The key to successful calcium reactor operation is a reliable feed pump, proper use and maintenance of the CO2 regulator, and clearing clogs in the media as needed. Some people add 15% dolomite (calcium magnesium chloride) gravel to their calcium reactor to better supplement magnesium and help calcium go into solution better.

In my experience, you will not experience RTN (rapid tissue necrosis) with a low level of calcium while keeping LPS and soft corals, just slower growth rates. In the case of SPS, you will get bleaching (faded colours due to a loss of symbiotic algae) which may lead to STN (slow tissue necrosis). This article touches on the vibrio bacteria that causes RTN & STN.

Calcium is a building block for us and our invertebrate friends. Our bones will get weak and corals will be stressed if we don’t get enough calcium, but it isn’t a rapid decline as some may indicate. I asked Bob Fenner from about the perils of a low calcium level and he concurred that it is merely a stress factor, not a direct cause of mortality.

Here are some handy calculators for when you are ready to start replenishing your depleted elements:


Mr.Wilson Writes on Sand Clean-up Crews

There are two schools of thought with regard to sand beds. One is to let it run its course and don’t add any critters that will compete with or consume denitrifying bacteria or other beneficial infauna (sand critters). This would exclude the usual suspects:

gobies (sand sifters & sand stirrers)
pistol shrimp
starfish (sand stars, serpent stars, crown of thorns)
sand dollars (never do well in captivity)
horseshoe crabs
nassarius snails
olive snails (amazing looking but they eat other snails)
garden eels

The opposing school of thought takes the Bob Dylan approach: like a rolling stone. A rolling stone gathers no moss, and neither does a moving sand bed … well algae instead of moss but you get the idea. Algae needs a stable environment (site) to set up shop. In addition to the poor real estate value of shifting sands, the abrasion of the sand aggregate removes/kills algae, evicting them from the site. In addition to sand movement, the larger sand dwelling macro organisms listed above consume detritus and micro organisms that break down and feed the nitrogen and phosphate cycles (nutrient cycles).

It’s really up to you to decide if you feel the sand bed can stay clean on its own merits or if it needs a team of janitors. The janitors tackle the issue of cleaning on a macro level, removing and reducing waste, while the infauna (sand critters) have a bacterial approach that reduces the chemical compounds that accumulate after the waste is left uneaten by the big guys up the food chain. In my opinion they can all find their niche as they do in nature. The two groups of beneficial organisms are not mutually exclusive and a more diverse food chain is always welcome. I just choose to limit that diversity to things that can’t eat me.

In addition to serving an important role in the food chain and biological processes of a reef, these sand dwelling denizens animate the aquarium and put perspective into the sand bed. They complete the picture of the natural reef we are trying to replicate. The sand is no longer a dead end bottom of the reef, but a doorway to a vital and vibrant benthic world. The benthos or benthic zone is not only an active place for biological filtration and chemical processes, but a home to some of the most fascinating reef organisms available. As far as sand critters go, there are two groups:

1) Sand Stirrers: These are organisms that move sand around to build burrows, crawl or swim through the sand displacing it, or dive into the sand at night as in the case of many wrasses.

2) Sand Sifters: These are the harder working janitors. This would include primarily gobies of the Valenciennea genus, commonly known as watchman gobies. These gobies pick up a mouthful of sand and rise up from the substrate (some more than others) as they move the sand through their gills, delicately sorting out food items (infauna). These fish should always be kept in pairs and even better with a commensal (symbiotic) pistol shrimp. The shrimp constantly extends a tentacle to keep track of the watchman goby that stands on guard for predators. In exchange, the shrimp maintains the sand tunnel in which they cohabit. It’s one of nature’s rare successful ménage è trois A couple of sand sifter watchman gobies can turn a green or brown substrate lily white in a day or two. They vary in efficiency and nuisance as well as adaptation to captivity. I recommend tiger watchman gobies (V. wardi) and orange spot watchman gobies (V. puellaris), not to be confused with A. guttata (orange spotted goby) who is an excellent sand stirring goby, but sifting isn’t in his contract (they don’t do windows either).

The bright green brittle stars from the Philippines can actually catch and eat fish. They “stand up” like a spider and wait for an unsuspecting fish to swim under. I use these starfish in the sump to take care of detritus. They are also good at cleaning dead coral tissue. These are the only non-reef species of brittle star I know of.

Chocolate chip stars are not reef safe, nor are pillow stars or general sea stars.


Mr.Wilson Writes on Chemicals and Test Equipment for Aquarium Maintenance

The liquid test kits by Lamotte, Hach, Merck, Salifert, Elos, and SeaChem are of good quality. Sometimes it is better to pick and choose individual tests from each company for ease of use and accuracy. As with the controller, a second opinion is vital as reagents can get contaminated or old and human error is unavoidable (e.g. “Did it say add 5 drops or 5 ml? Better add more just to be on the safe side.”)

Here is the amended list:

1) Digital PH controller for calcium reactor body to govern CO2 dosing.
2) Digital PH controller for system water to override CO2 dosing and/or dose kalkwasser and sodium bicarbonate.
3) Digital Dissolved Oxygen meter. You can move it around, but it should get homogenous readings throughout the water column. You will, however, get lower readings in slow flow reactors and deep sand beds. Order extra probes as they don’t last forever and cannot be calibrated.
4) Digital salinity meter.
5) Refractometer and glass hydrometer for double checking salinity.
6) Liquid ammonia test kit.
7) Liquid chlorine test kit for bleaching fishroom tanks.
8) Liquid nitrite test kit.
9) Liquid nitrate test kit (premium low range).
10) Liquid calcium test kit (premium brand).
11) Liquid magnesium test kit (premium brand).
12) Liquid carbonate hardness test kit (premium brand).
13) Digital dual TDS meter for adding pure freshwater; one for the water entering the deionizer and one for measuring the water exiting. It’s also nice have a hand held TDS meter to know what the municipal water source is like, as it shifts seasonally in most areas.
14) Digital redox/ORP controller.
15) Digital phosphate photometer (Milwaukee or Hanna).
16) Liquid phosphate test kit (low range Merck).
17) Liquid iodine test kit (premium brand).
18) Liquid strontium test kit (premium brand).
19) Liquid silicate test kit (premium brand).
20) Liquid copper test kit (free copper & total copper).
21) Quantum/PAR meter.
22) Scientific analog thermometer to calibrate digital meters.
23) Titanium ground probes.

At some point in time you should also start stocking up on chemicals to correct the parameters you are testing such as:

1) Hydrochloric acid (cleaning & lowering pH)
2) Calcium hydroxide (raising & maintaining calcium & pH)
3) Calcium chloride (raising calcium quickly)
4) Sodium carbonate (raising carbonate hardness & pH)
5) Sodium bicarbonate (raising carbonate hardness & lowering pH)
6) Peroxide (raising dissolved oxygen & redox as well as disinfecting)
7) Dry salt mix (raising salinity)
8) Sodium hypochlorite (pool/household bleach for sterilizing filters, equipment and holding tanks)
9) Sodium thiosulphate (neutralizing sodium hypochlorite/dechlorinating). Buy Seachem Prime as it also detoxifies ammonia and nitrite. Have it on hand for emergencies.
10) Potassium permanganate (disinfecting equipment corals & fish, as well as neutralizing medications)
11) Lugols iodine (disinfecting corals & fish)
12) Formalin (treating fish parasites)
13) Malachite green (treating fish parasites)
14) Nitrofurazone (wide spectrum antibiotic)
15) Neomycin (wide spectrum antibiotic)
16) Isoniazid & rifampin (fish TB treatment)
17) Quinacrine hydrochloride (protozoan/cryptocaryon ich treatment)
18) Metronidazole (protozoacide & antibiotic)
19) Chelated or ionic copper (Mardel Coppersafe or Seachem cupramine)
20) Methylene blue (aids to clear gills of parasites in bath)
21) Piperazine & Dylox & praziquantel (dewormers)
22) Rubber gloves, disposable surgical gloves, droppers, scientific glassware, tweezers, grabbers, nets, flashlights,
23) Parasite eating doctor fish and cleaner shrimp for the acclimation tanks.
24) Flat worm medication. (Salifert Flatworm exit/Dylox).
25) Red bug medication (Interceptor/Dylox).
26) Iron and manganese based macro algae supplement.
27) Activated carbon.
28) Granular phosphate remover.
29) Fragging tools, glues, and plugs, rubber bands, cable ties and tape.
30) Floating clear acrylic viewing box for looking at the tank from the top down.
31) Acrylic buffer and polishing kits.
32) Whiteboard, notebook & labels for fishroom tanks.
33) Fish food, auto feeders, brine shrimp eggs and hatcheries, phytoplankton culture device, rotifer tanks etc.
34) Microscope or magnifying glass.
35) Algae removing sticks, single edge razor blades magnets & scrapers.
36) Gravel cleaning hose and gravel separator. Siphon hoses, strainers, water scoops, utility pumps, buckets, heaters and sieves.
37) Fish bags rubber bands and insulated styrofoam shipping boxes.
38) Feeding tubes and syringes.
39) Turkey basters and powerheads mounted on poles to blast detritus from the rocks.
40) Portable diatom filter.
41) Pest traps for worms and parasites.
42) Fish traps for fish that become pests or need to be removed for treatment.
43) Seachem ammonia alert badges for the fishroom tanks.
44) Ammonium chloride & sodium nitrite for cycling tanks.
45) Bacterial culture for cycling tanks.
46) Strontium for maintaining NSW levels.
47) A safe place to store all this junk, especially the next item.
48) Vodka and lots of it.


Mr.Wilson Writes on Acclimating New Fish

I use the hydrochloric acid (pure version of muriatic acid) method of acclimating fish. The first time you add the acid, the buffer system bounces back up in a few hours, but subsequent dosing lasts longer as the buffer system is depleted (calcium and carbonates fall out of solution). I tried using phosphoric acid in the past, and in addition to the possible toxicity of the phosphorus, it forms calcium phosphate as the two ions bind and fall out of solution. The result is a milky snow of precipitate in the water (not good). I had a CO2 dosing system at one point in time but found it to be impractical for large systems. The benefit of a CO2 system over acid is that you have full control over how quickly the pH returns to NSW (normal) levels. The other benefit is you can assure that your acclimation water has the same gas concentration as the shipping water. This helps certain fish that have damaged or poorly developed swim bladders (Boyle’s law). Fish packed for over 12 hours will typically have a shipping water pH of 6.5-6.8. This is good news because ammonia is non-toxic at this level. Ammonia detoxifier chemicals like Kordon Ammquel help get the fish safely through the first 12 hours or so.

I use ice to drop the system water temp to match that of the shipping water, which is typically 68-72°F. Fish acclimate better when going into slightly lower salinity water so it works out well with hyposalinity commercial holding systems. Fish adapt poorly to increases in the osmotic pressure of higher salinity water so the salinity should be slowly raised over the three week acclimation and treatment period before being introduced to the display aquarium.

I use a few prophylactic medications and UV sterilizers in the acclimation system. No carbon, ion exchange resins or protein skimmers should be used. An established biological filter is vital as there should be no rock or calcareous (calcium-based) substrate in the acclimation system. A bare bottom tank is best so parasites can be removed.

Floating the bags is far too stressful for the fish, and opening the bags and letting them remain in the shipping water as it becomes toxic as the pH rises will cause gill damage or mortality. Shallow styrofoam boxes tipped on an angle with inadequate, unreliable drip lines is also too stressful for all involved. These jerry-rigged systems are common at LFSs and employ contaminated boxes, no air lines for water movement and bright lights that further stress the fish out during the acclimation process. You want the fish to go from the bag to the holding tank without even knowing what happened. Turning the lights off and working in a dimly lit room helps. Catching the fish with a gloved hand or scope and keeping it submerged also makes a big difference. Fish nets are a chief cause of fish injuries and subsequent infection. Marine fish have not adapted to breathing out of water for even a few seconds. Freshwater fish have adapted some tolerance to breathing atmospheric air as they live in environments near the surface and where dry seasons create low water levels.

Overcrowding new arrivals is another popular mistake. Fish to fish disease transmission, aggression, oxygen deprivation, water contamination, and simply bumping into each other makes spreading the fish out over more tanks the wise choice. PVC pipe hiding places are another must.


More on Acclimating New Fish

If you are picking up fish from the LFS down the street and the fish are only in transit for an hour, then a drip system is adequate, but long packing duration requires more delicate acclimation to ease the stress of extreme water conditions.

I still don’t like the idea of floating fish bags as they may have medications and chemicals from a packing counter or holding tank, particularly copper. The fish are also stressed by the pinched corners of the bag and are forced to inhale oxygen from the surface as the bag rolls around in the water current. Bags can float under bright aquarium lighting, fish can pick on the new ones while they are still in the bag, and in some cases the bag collapses eliminating all gas exchange which can kill a fish quickly.

I think we all agree that the shipping water with the fish has no business in our systems. In addition to it containing chemicals and medications, it harbours bacteria and parasites and the water quality at fish stores is less than pristine. Every time a wholesaler imports a fish, he imports diseases that are unique to that part of the world and even that part of the reef. Fish stores are at the end of the chain of distribution and are therefore a united nations of fish diseases with every possible pathogen represented.

In Peter’s case as with people who buy from distant suppliers over seas or in another province or state, the fish will be in that shipping water for at least 24 hours. As the fish breathes it converts O2 into CO2. The CO2 is in a liquid form (carbonic acid) which, like any acid, lowers the pH. The longer the fish is bagged, the lower the pH. On one hand a pH of 6.7 – 7.0 is stressful to the fish, but on the plus side it takes the toxic ion out of ammonia rendering it harmless.

So now you receive your fish at home and the first thing you do is open the bag and let that “bad” air out and let “good” air in – wrong! As soon as a gas exchange occurs, the pH is rapidly driven back up to 8.0 – 8.2. This increase in pH is not only a shock to the fish, but a deadly poison as the toxic ion of ammonia goes back into solution. I’ve seen fish orders die in 20 minutes after traveling for 48 hours successfully.

One solution is moving the fish directly into new water with matching parameters (pH, temperature, salinity, etc.). The small scale alternative is to add ammonia neutralizing chemicals such as Kordon Amquel. Kordon has another helpful product called Novaqua that helps restore a fishes slime coat while removing nitrite, heavy metals, etc.

The problem with drip systems is in the execution not the theory. People tend to use containers that aren’t food grade so chemicals can leach out, especially when we are adding acid or oxidizers. LFS’s have a bad habit of using dirty Styrofoam boxes that have been used many times for everything from holding tanks to porta-potty, on both sides of the globe. Styrofoam containers are too bright (white). Fish are very sensitive to light during acclimation. Styrofoam containers are also to wide, requiring too much water to fill the bottom so LFS workers prop them up at an angle to concentrate the water in the corner. This works fine until it falls with the weight of the new water.

Another common problem is drip lines that stop dripping or drip too fast or fall out of the acclimation container and pee on the floor. Air lines are equally as problematic. Fish don’t like the sound, air bubbles can cause nitrogen bubble disease (tiny air bubbles trapped in the gills), and air lines are notorious for floating up and out of the water. This may sound implausible for your pair of clowns you just brought home, but I’m talking about larger scale operations where you lose track of what you have and where it is. Working in the dark late at night (from an overseas flight) compounds the problem.

Drip systems also have an issue of jumpers. Shallow containers with fish darting around and smashing into each other is a recipe for jumping. It’s like that hyperspace button in Asteroids for those of you old enough to remember it (or young enough to have the capacity for long term memory). The fish hits the hyperspace button when things look grim.

The ideal system for acclimating fish is a dark room with prepared tanks set at the parameters of the shipping water. Fish acclimate better to slightly higher water temperatures than they do to slightly lower temps, but i would go with the Goldilocks method of getting the porridge just right. Fish should undergo a maximum temperature swing of 1°F over a 24 hour period. The temperature will likely be 68-72°F so ice can be used to match it initially. Maintaining a cool temperature over a few days can be a bit of a challenge without a chiller. Keeping acclimation tanks on a concrete floor or in a climate controlled room helps. The ice can be kept in bags if the salinity is already matched, but I have found that shippers usually have a hyposalinity (low salinity) of SG 1.017 – 1.019. From time to time they come in with a hypersalinity (high salinity) so salt should be predissolved in a slurry that can be added to the acclimation tanks. A low salinity helps reduce parasites and stressed fish will feel more comfortable than in high salinity where they need to constantly pump the salts out of their bodies. A salinity of 1.019 feels like 1.022 to a stressed fish. Fish also acclimate much better going into lower salinity water than into higher salinity water due to reduced osmotic pressure. Keep in mind the fish will be stressed as the salinity goes up when they go to the display tank. This is why a regular water change over the three week acclimation/quarantine is a good idea.

By adding acid or CO2 to an acclimation tank or system you can slowly bring the pH up over 24 hours or longer for sensitive fish like puffers. Drips are hard to maintain for more than a few hours. I go with a hybrid of mixing shipping water and acidified (pH corrected) water while acclimating shrimp and lobsters. Anemones are another one that need lots of time to adjust, particularly when they turn themselves inside-out. The key is to maintain excellent water quality (no ammonia or nitrite and high levels of dissolved oxygen) while acclimating. Sometimes a drip or hybrid system can’t give you the optimum water conditions and stress-free environment the fish need.

Big commercial orders often take 6-12 hours to unpack so the temperature and pH can shift while you work. I check a sample bag in every box to make sure I’m still on target. The boxes from the Philippines are double boxes with one on top of the other. During winter months the bottom box can be 5 – 10°F cooler than the top box (especially if you use Northwest Airlines who fly everything through Detroit). Each airline uses its own hub to route flights. Pick one that is direct and with a moderate climate. In the summer you can use an airline with a hub in Chicago, not Tampa, while in the winter Tampa sounds a lot more tropical fish friendly than Chicago. Another variation exists with different sized fish. Damsels ship with a small splash of water while large tangs, angels and butterflies ship with lots of water. The bags with lots of water will have a higher temperature as they have a greater thermal mass, thus slower to swing when exposed to the cold. Keep in mind, the fish are stuck on a runway in a tropical country for hours where they are exposed to direct sunlight, then a cool shipping compartment, and then whatever your local airport has to offer. It would be nice to pack a thermometer with a 24 hour memory in a fish box.

Once the acclimation/quarantine tank is ready, pull up a seat and start cutting bags with sharp scissors and remove each fish by gloved hand to an appropriate tank. Aggressive fish and fish that may transmit disease to each other should be segregated. As much as chromis look cool in a school, they should be isolated to prevent or at least isolate white band disease and vibrio which they are susceptible to. Clownfish also do best on their own to prevent the spread of brooklynella.

I’ve tried numerous methods of acclimation and have found that the pH correction method is the best for the long and short term health of the fish. Within a few hours the fish are up and swimming around, while the drip method leaves them laying on their side breathing rapidly for a few days. Once delicate gill tissue is damaged (ammonia burn or lack of oxygen) the fish may never fully recover.


Mr.Wilson Writes on Water Changes

There is no benefit to a hopper system that mixes saltwater because it is a simple process for the aquarist to safely carry out on their own. I also believe that inviting machines to take over potentially dangerous tasks like changing water invites the possibility of malfunction and subsequent disaster. No machine, or person, is infallible.

I advocate for a hybrid part man/part machine system. A manual valve should be controlled by the aquarist if and when a water change is deemed in order. If nothing else, this forces the aquarist to inspect the tank closely and possibly detect a problem the timer device will not. On the other hand, we can employ machines to safeguard from human error. Once manual or mechanized valves are opened, a timer or metering device can be used so we don’t forget that we have commenced the water change. It’s sounds implausible, but the phone rings, your wife asks you to do something, or you wander off on your own leaving the tank filling and draining. Of course a machine is only as good as our programming prowess so the problem may still lie somewhere between the chair and the keyboard.

The benefit of a manual water change is you can remove detritus with the water. There is a lot more “stuff” in detritus that has settled in your rock work, sump, and overflow box, than the amount of “stuff” in free flowing water in the system. The incoming water is typically a degree or two cooler than the system water so it will drop to the bottom or stay at one end of the display tank, making it easy to remove “old” water without taking some “new” water with it when filling and draining at the same time.

There are many ways to skin the water change cat. First you must mix the salt well, match the parameters (supplementing calcium or other elements may be necessary), match the temperature and make sure the water is well aerated with an air lift. Using a Metering pump to add the water is the safest method because it limits the maximum amount of water that one can add over a given period of time. The model I use moves a maximum of 8 gallons per day and can be dialed down to 2 GPD (the current peristaltic metering pump is too noisy, so I’m switching brands – maybe “Blue-White” or an aquarium specific brand). If I forget to turn it off, it can’t possibly add too much water. However, if you add the new water too slowly, it will affect salinity as it will interfere with freshwater evaporation top-off. The “new” water should enter in the overflow box, first compartment of the sump, or into a refugium so the water mixes well before entering the aquarium and reaching delicate corals. Sometimes chemicals fall out of solution when heated up or mixed with other water so a slow introduction is beneficial.

Alternatively, a solenoid valve (electronic valve) and mercury switch (electronic float switch) can be used to deliver the new water (via gravity feed or dedicated pump. A second (higher) solenoid shuts off the metering pump or solenoid when the desired water level is achieved. A secondary mechanical float valve mounted above the operating water level of the system is a good idea as an absolute fail-safe. A bulkhead that drains the sump if it overflows is your absolute – absolute fail-safe

A more common method for adding new water during a water change is to use a hobby pump (powerhead or external pump) so the task is done in a short period of time, minutes rather than days. This method makes it easier to focus on the task, but if you forget, things go bad more quickly. You can use marker lines on your reservoir or a water meter to establish how much water you have added. I like to use a high volume mechanical float valve (livestock float valve) at the end of the fill hose (in the sump) so it stops the flow when you reach a predetermined water level.

That covers adding the new water, now you need to remove the old water. It is more efficient to remove the old water first, before adding the new water, but make sure you don’t drain more water than you can replace, or let the sump run dry and blast microbubbles into the tank. As I mentioned earlier, this is your opportunity to siphon or pump out detritus that has accumulated. You can fill a container (with water volume lines marked on it) with the old dirty water so you know how much you have removed. Once you’ve reached your target number of say 50 gallons (the size of a plastic shipping drum), you can stop and allow the system to continue filling until 50 gallons has been replaced. Using two identical containers for holding and measuring new and old water makes it easier to know when to start and when to stop. A secret stash of new water is a good contingency plan.

The other “best way” of draining the old water out of your system is a passive method of simply allowing the extra water volume to overflow through a bulkhead mounted in the sump. With this method you only need to monitor and limit how much new water you are adding, as the draining is self regulating. What goes in, must come out. This is a K.I.S.S. method. You limit your input of new water by the amount available to add (your premixed 50 gallon drum). You eliminate any possibility of draining too much by letting gravity take care of that issue too. The return pump, closed loop pumps, and protein skimmer don’t need to be adjusted or turned off so you don’t invite the chance of failure on restart or forgetting to do so. The sump water level never lowers so you won’t stir up detritus or send microbubbles into the display tank. The only down side is you don’t export/remove detritus and you may lose some of your new water with the old. Because colder water sinks to the bottom, it is a good practice to add slightly cooler water so it doesn’t float on the top and overflow out of your system through the drain standpipe or bulkhead.

Another common practice is to drain all or part of a sump or detritus settling drum and fill it back up to the original level with new water. This method limits detritus storms flowing from the sump to the display because the return pump is shut off during the process. In some cases, I go as far as to use a shopvac (wet vacuum) to remove sludge from the dark recesses of the sump. When you are done, let the dust (detritus) settle and turn the return pump back on. This is another area where we can employ timers as watchdogs for our own stupidity. Your aquarium controller will have several pump sequences that shut down for a predetermined amount of time. If your water change process takes half an hour, you can set the pump to come back on in an hour in case you forget to do so. Of course, this too invites the possibility of mechanical failure, so I prefer to use the alarm in my phone to remind me.

A wise choice is to use illuminated power outlets, as this visual aid limits the dangling cord or controller bypass one may overlook. For those of you who don’t want to spend a lot of money on such an elaborate electrical system, there are some cheap illuminated plug adapters and power bars with individual illuminated switches. AC/DC night lights (no, not the ones with the Angus Young schoolboy outfit ) are also a good addition because they light up and catch your attention when the outlet has shut off. Another low tech trick is to plug in a clock that will be behind by however many hours the power was off for. Often, the power goes off for a short period of time, and the aquarist isn’t even aware of it. Once you know, you can trouble shoot your system and take appropriate action.

Having said all that, peristaltic metering pumps like the one I linked earlier and aquarium controllers are very reliable. These pumps cannot possibly start a siphon, or pump faster than the preset rate. It likely uses one motor to both add and subtract water so the quantities should be bang on. These types of pumps are used in high tech industry and for medical purposes so they have to be reliable. I’m not about to say a jerry-rigged daisy chain of DIY devices is more reliable. I just agree that you can’t completely remove the human element, no matter how flawed.


More On Water Changes

In my opinion water changes are good for the following purposes, in order of importance/effectiveness:

– removing detritus
– reducing/diluting secondary metabolites (algae & coral toxins)
– reducing/diluting heavy metals, or what we call trace elements in the aquarium hobby
– reducing/diluting vitamins
– reducing/diluting nitrogen (ammonia, nitrite, nitrate)
– reducing/diluting phosphate
– reducing/diluting bacteria
– reducing/diluting TOC

Water changes are limited by the percentage you exchange. A 10% water change removes 10% of the “bad stuff”. The exception to this is detritus removal, if you are vacuuming the substrate, blasting out rock work and vacuuming the sump. Water changes do not effectively replenish water chemistry, as it is limited by the same percentage issue. In other words, a 10% water change only assures that 10% of the total water volume has the right proportions of calcium, carbonates, magnesium, and all the other “good stuff”. While it is nice to remove some of the bad stuff, filtration devices are more efficient and calcium reactors and chemical dosing assures that 100% of the water has the proper water chemistry (good stuff).

Water changes can cause harm if they aren’t carried out diligently. Some of the negative aspects of water changes are:

– reduction of probiotics (bacteria & plankton)
– introduction of impurities via source water, salt mix, mixing tools or hose
– introduction of excess trace elements and vitamins from salt mix
– temperature fluctuation
– salinity fluctuation
– PH, KH, calcium, magnesium etc. shock from bad salt mix
– classified/non-homogenous salt mix due to partial bucket or bag use
– old, clumped/compromised salt mix
– exposure of corals to atmospheric air
– partially dissolved salt mix
– poorly aerated salt mix
– accidental overfilling system
– accidentally over-draining system
– sand bed disturbance releasing hydrogen sulphide or depleting DSB infauna (beneficial organisms)

The main issue with water changes is they need to be calibrated to the demand. If you have “x” amount of nutrients building up in your system, then you need to do water changes according to that demand. A 10% water change will reduce your 20ppm nitrate down to 18ppm, but your residual nitrate accumulation may be at a faster rate than your weekly or monthly water changes. We aren’t talking about a static amount that you can slowly chip away at, unless you have filtration devices and nutrient export of other sorts to make up the difference. If that is the case, water changes may not be necessary, and they are clearly the most expensive and least effective method of nutrient export.

We know that zero nitrates and phosphates can be maintained without water changes through carbon dosing, DSB, GFO and refugia to name a few. We also know that water chemistry can be maintained without water changes, and that there is an excess, not a deficit, of trace elements. Why add trace elements (heavy metals) when we statistically have too many? Most reef tanks don’t require physical removal of detritus, including many of the tanks that receive major and frequent water changes. This only leaves secondary metabolites as an agent that we need to export. It is possible that this is enough justification for water changes, but it is equally possible that they are removed more efficiently through UV, ozone, protein skimming, mechanical filtration, mangrove trees, macro algae, carbon, bacterial assimilation, biological assimilation by micro organisms and coral, or simply time.

In evaluating any procedure you must first establish what you are trying to accomplish and why you are doing so. If water changes offer something that you are not getting with your current regimen, and you feel there is a demand in the first place, then by all means do so. On the other hand, if you feel that your application has all of these criteria covered and see no need for adding trace elements & vitamins, then water changes may not be a cost effective method of maintaining your reef.

The bigger the tank, the less you rely on water changes, and vice versa. A reef tank of 50 gallons or less, can be maintained with major weekly water changes at a lower cost than purchasing UV, ozone, calcium reactor, dosing systems, a refugium and mechanical filter. You can reinvest the capital and operational costs into a good source water filter, salt, and a water changing system. Once you get over 200 gallons, water changes are less appealing.

This doesn’t mean you can stop doing water changes without consequence. Many people claim that their tanks look better after water changes. If you have a good system and are confident that it can be somewhat self sustaining, then slowly reduce water change frequency or volume. If you see negative repercussions, then resume water changes as before.


Mr.Wilson Writes on Flow To/From the Sump

People ask me all the time, “How much flow do I need to the sump?”, “Where should I put the overflow box?” or “Where should I locate the return line?”. The answer is never simple because each aspect is directly affected by the other. I like to start at the beginning and look at what the protein skimmer’s demand for flow is.

Let’s take a step back and think about what we are trying to accomplish before we decide how we want to get there. The main purpose of moving water from your display tank to the sump is to process it in a protein skimmer and a few other devices. The same process that goes on in your protein skimmer occurs with your surface skimmer. You are separating oils/surface active agents (surfactants) from the water. You have to treat the display tank like an oil slick (but not how the BP engineers and shareholders do). When skimming oil, you want to use a very thin “scoop” so you collect concentrated oil, and as little water as possible. You can accomplish this in two ways.

1) Set-up a surface skimmer that has a maximum amount of surface area. A surface skimmer with no teeth will have double the surface area and subsequently collect water that is twice as concentrated with surfactants.

2) Use a return pump that has a relatively slow flow so the water cresting over the overflow box is half as thick = twice as rich in surfactants.

Both of these factors influence the surface tension of the water traveling over the surface skimmer wall. The overflow box works the same way a water strider bug (those bugs that float and walk on still water) increases the surface tension of the water under it’s legs. The teeth in an overflow box increase the water tension in the same way thus limiting the free flow of water over the box. This effect is in addition to the shear surface area of the box diminished by having the teeth.

A better barrier for overflows than teeth is an eggcrate strip that sits parallel to the overflow box wall, positioned 3/8″ back toward the box and away from the tank. Any snails will be stopped by a single continuous 3/8″ horizontal slot, rather than many 3/8″ vertical teeth. I like to use eggcrate because if the entire slot somehow magically plugs, the overflowing water will rise up and find its way through the holes in the eggcrate. This method compromises nothing, while more than doubling overflow efficiency. Unlike teeth, a single slot is unlikely to plug with filament (hair) and macro algae.

Overflow Design

Overflow Design

The drawing is a general guideline and not an absolute. The protein skimmer can be fed directly by the display tank drain line, or drawn in by the skimmer pump (be it single pump system or separate feed pump).

Regardless of the actual skimmer feed method the skimmer reservoir water level will be variable. The gravity feed of the sump is regulated by the sump return pump. Whatever enters the display must drain to the sump. If the skimmer reservoir level drops, the excess water in the rest of the sump will “flow backwards” into the skimmer reservoir. The skimmer reservoir can’t run dry because the sump will always have water to fill it back up form one side of the partition or the other.

Another way of looking at it is to consider that your sump return pump moves lets say 1000 GPH, and your skimmer pump overpowers it moving 1200 GPH. That excess 200 GPH will not be pumped up to the display tank because we are limited to 1000 GPH going up. That 200 GPH will rise in the reservoir until it flows into the emptying skimmer reservoir. In summary…

– 1000 GPH overflows by gravity into the skimmer reservoir/sump.
– 1200 GPH overflows the skimmer reservoir via the protein skimmer.
– 1000 GPH returns to the display via the sump return pump.
– 200 GPH overflows from the sump’s second compartment where the return pump is, to the first compartment (moving “backwards”) where the skimmer is (skimmer reservoir).

If the skimmer pump on that same hypothetical system only moves 800 GPH, the following would occur…

– 1000 GPH overflows by gravity into the skimmer reservoir/sump.
– 800 GPH overflows the skimmer reservoir via the protein skimmer.
– 1000 GPH returns to the display via the sump return pump.
– 200 GPH bypasses the skimmer and overflows over the first partition (skimmer reservoir) into the second reservoir.

If you get the output of the skimmer pump and return pump exactly the same the water level in the skimmer reservoir will only pass over the partition to the second section of the sump via the protein skimmer.

The drain configuration should really have two dedicated holes but I posted this configuration to show you how to solve the common problem of plumbing a tempered tank with just one drain hole. You could also use a 1.5″ pipe as the siphon and a 3/4″ as the emergency and to pick up the slack.

It’s a similar system to Beananimal’s or Herbie’s. One siphon is enough to drain the whole load, but siphons have a tendency to vary in suction, so you set it to overload the siphon slightly to assure the siphon won’t over siphon and lose prime, and the secondary drain can manage the variation as drain speed. If the siphon slows down or clogs completely, the secondary 1″ line eventually becomes a siphon and drains very quickly. The smaller the line the better when it comes to starting/priming a siphon. A siphon moves water exponentially faster than a gravity drain due to water surface tension.

The set-up I like for return plumbing, uses end to end flow across the surface as I described in an earlier post. If you are already committed to a central (back wall) coast to coast overflow, then you would be best to use about 4 return effluent ports, all located at the bottom of the tank at the back panel pointing forward, toward the front panel. Make sure you have good siphon break holes or a check valve siphon break above the water level (flap pushed closed while water is on, and flap dropping open letting air in when water flow is off. This configuration will give you a barrel role effect (circular flow), with water mixed well before it is surface skimmed. Water goes along the substrate, hits the front wall, travels up the wall, and then across the surface to the overflow on the back wall. This kind of a set-up works best for jellyfish tank kreisels and pseudo kreisels where the corners are curved to help with inertia/kinetic energy (less resistance).

An L shaped tank like Peter’s needs to be fed at the centre with all ports pointing toward the overflows at either end. You have to treat it like two tanks stuck together in the middle. If you don’t go this route, you get chaotic flow which leaves oils (surfactants/hydrophobic proteins) on the surface that cannot be easily skimmed. You get a “no man’s land” in the centre where the surface water sits in limbo, not knowing which way to go. You can do a visual test (look up from the bottom and see if there are oily pools of “stuff” that aren’t being turned over or skimmed, in addition to the 30 second flake food test (it takes less than a minute ).

In summary, don’t use teeth and limit return flow to the minimum requirement which is the throughput rate of your protein skimmer. Any more than that will reduce efficiency of overflows, overtax drains, increase noise of water coming and going, add heat and energy use due to larger pumps, and increase salt creep and microbubble formation in the sump. Return ports are to be tuned with your overflow box to create either end to end flow or a barrel role (gyre) up and back across the surface to the overflow with its waiting open (toothless) mouth.

If you really want a magic number it is 1.3333 x the volume of the tank. This is the number that P.R. Escobal came up with as a the optimum flow-through/throughput for a protein skimmer. This is providing the protein skimmer is properly sized for the aquarium. That same number 1.3333 x is also correct for UV sterilizers according to Escobal and according to me, the right flow for a refugium. Unlike Escobal, I don’t have any fancy mathematical formulas to prove that, but the consensus in the community is “low flow”.

A more accurate method for determining return pump size is to match it to the protein skimmer input pump or gravity feed rate if your skimmer is fed directly by the display tank drain. If your protein skimmer processes 500 GPH, as most do, then that is your target number for the return pump. Any more will allow water to pass through the sump unfiltered, any less will diminish the efficiency of the protein skimmer as it process the deficit twice. For example, if your return pump moves 400 GPH, then 100 GPH will be processed twice before returning to the display tank. If your return pump moves 600 GPH, then 100 GPH will bypass the protein skimmer.

You should plumb your skimmer so all of the water entering the sump must go through it before moving on to the next section. This can be achieved by directing your protein skimmer effluent/out line so it delivers the processed water over a glass partition. This way all incoming water is processed and done so only once. If your return pump is stronger than your skimmer pump you will lose the difference in bypass as water overflows over the glass partition without going through the skimmer to do so. If your return pump is weaker you will process the difference twice as the processed water migrates backwards into the first (protein skimmer) section of the sump, flowing the reverse direction over the glass partition.

Some protein skimmer designs like Becketts require very high flow (often 10 x the volume of the display tank). In this case the pump will move well over the magic number of 1.3333 x the volume of the tank. For these applications, the UV sterilizer, refugium, and media reactors all need to be on a bypass.

Another quick point about protein skimmer flow-through/throughput rates: manufacturers have a limited number of base motors to use in their skimmer pump design. One of the current leading powerplants is the Sicce PSK 2500, which moves 660 GPH when used as a needlewheel skimmer pump. The other popular motor is the Askoll 1500, which moves 500 GPH when used as a needlewheel pump.

You will see these same pumps used by many manufacturers for skimmers rated for 100 – 500 gallon tanks. The truth is, it’s cheaper to use an oversized pump than to engineer and custom build a smaller (right-sized) pump. It’s also cheaper to use one pump to feed the skimmer water and simultaneously generate bubbles. Due to these shortcuts, you will find that some manufacturers break the rule of 1.3333 x the volume of the display tank flow through/water feed rate.

A one pump (jack of all trades, master of none) skimmer is not as efficient as a closed loop skimmer that uses one higher volume pump to generate bubbles and a siphon & gravity drain from the tank to feed water through it. This kind of system assures a 1.3333 feed rate and full control of bubble production without interfering with the feed.

It’s hard to find and believe water flow rates for skimmer pumps. The Sicce 2500 gets its name from the 2500 LPH, or 660 GPH, flow it produces as a water pump. I don’t know if they really take the huge reduction in water movement from drawing in air into consideration. The more air you suck in, the less water you move, and the hotter the impeller/needlewheel gets. These pumps have a range of 1000 – 2400 LPH air draw depending on your needs and how hard you want to push them. Bubble size and subsequent stability is also variable along the curve. I can’t find real numbers but the actual water movement is likely 200 – 400 GPH? For whatever reason, all of the ads for Sicce PSK 2500 needlewheel pumps claim it moves 660 GPH water.

The Askoll/Laguna 1500 pushes… you guessed it, 1500 GPH, or 5678 LPH. I found a few resources that claim 450 – 500 GPH of actual water movement when it is run as a needlewheel pump, but these are likely to be estimations. Royal Exclusive claims that their Red Dragon Askoll 1500 draws 1000 LPH air and moves 2000 LPH (528 GPH) water. I have also heard reports of up to 3400 LPH air draw with the Askoll 1500 using a threadwheel/meshwheel. There’s no way you can add that much air (displacement) and still move 500 GPH water.

The protein skimmer market wants to hear about air draw, and to a lesser extent energy consumption, and nothing else. It’s like focusing on horsepower instead of torque. As the saying goes “torque wins races, horsepower sells cars”. In our case torque = contact time, bombardment (air against water), and bubble size (the smaller the better, more surface area and stability). The horsepower in the skimmer trade is air draw. Throw a $10.00 Dwyer RMA22 air flow meter on it and measure your “efficiency”.

There are many ways of fine tuning efficiency. Having a smooth transition as the foam rises up the neck decreases premature bubble merging and popping, such as experienced with a cone or partial cone skimmer. Right-sizing the neck is also important. If the neck is too wide the bubbles can’t climb and pop before reaching the top, releasing their protein catch. If the neck is too narrow, the bubbles merge as they are over-concentrated and jammed together.

Having the water flow one direction while the bubbles flow another (countercurrent) is a lost art of bombardment. These days a single pump system moves water and air together in one direction. Having a slightly higher salinity (1.025 instead of 1.023 or 1.024) will help you skim more. Some people draw the air for their skimmer from a drier, cooler source away from the aquarium, but often this restricts air intake due to friction loss. Ozonizers without air driers or air pump feeds (venturi intake to skimmer only) also restrict air intake volume.

The other largely overlooked issue is feeding the skimmer. The water leaving (draining from) the display should go directly to the protein skimmer, do not pass go, do not collect $200. This will assure that the “stuff” you have just skimmed from the surface of the tank continues to get “skimmed”. It also makes sure detritus (particles) don’t settle in the first compartment so the protein skimmer gets a fair shot at removing it. As I mentioned earlier, you need a “first in, first out” (FIFO) system. The water that enters the skimmer first should leave first so all of the water is processed for the same maximum amount of contact/dwell time. If you set up the skimmer effluent (out) to send the processed water downstream to the next compartment in the sump, it allows the skimmer to draw new unprocessed water in without losing the FIFO order.

Too often aquarists spend $1500 on a premium protein skimmer then use an inefficient, undersized, dual overflow box (one at each end of the tank) with teeth. Then they drop the protein skimmer randomly in the first compartment of the sump or worse, at the wrong end of the sump (last compartment before returning to the display). When you let your protein skimmer randomly suck in the same water it has just processed repeatedly, you throw all of the “efficiency” you have payed dearly for out the window. Some of that water may run through the skimmer 5 times before it is allowed to return to the aquarium, while the rest of the water bypasses it entirely. Some systems are more or less “water movers”, rather than filters, simply juggling the water. A FIFO system doesn’t cost a penny to set-up, and has no ill affects on the system.

Running two skimmers is always a fun exercise. May the best skimmer win, but having two gives you a back-up plan. If one is a little off, the other should pick up the slack. I also feel two small skimmers are more efficient than one big one. It’s a bubble stability thing.

You should have no problem drawing air through the ozonizer with the skimmer air intake, but the added friction may diminish the total air draw somewhat. Ozone also decreases the stability of skimmer bubbles, but you make up for it with the high oxidization rate of O3 (ozone). This will yield a more yellow and less viscous (thick) skimmate. Having one skimmer with ozone and one without will be a distinct benefit. Each skimmer has its specialty.

ORP (Oxygen Reduction Potential) is a magic number that isn’t always consistent with success or lack thereof. Technically it is the water’s ability to oxidize organics. It’s kind of like our body’s cardiovascular fitness. A high ORP og 350-400 will help biological filtration and speed the rate of assimilation of “bad stuff” (organic waste).

I would certainly try an air pump and air drier. Buy an oversized drier or two of them to aid in maintenance. There are reports of nitric acid forming in ozonizers that process damp air, but I don’t fully comprehend the repercussions myself.

As ozone kills microorganisms and breaks down organic matter it is easily picked up in the skimmer bubbles as these molecules are strongly hydrophobic (attracted to air & repelled by water).

Calcium hydroxide, calcium chloride, and calcium oxide are all desiccants (air driers) that can be recycled as calcium buffer after they are spent.

There are two types of pumps available: pressure and volume. Volume pumps are designed for pools, spas and ponds and have limited head pressure (ability to push the water high or through small diameter pipe). The pipe diameter should be a minimum of 1.5″ or split into a minimum of three 1″ lines.

Pressure pumps can push water much higher and work against considerably greater friction caused by smaller diameter pipes and the numerous fittings (elbows, tees, valves, etc.) it takes to get the water where you need it. Rather than increase the HP of your pumps, you may want to consider increasing the pressure rating. Pressure pumps are frequently used for industrial applications so they are chemical rated for corrosives like salt water. Your volume pumps have a direct drive shaft connected to the impeller. This is an area where the bearings and shaft can corrode. There are special silicone carbide seals available that will last up to ten years, but the standard issue seals only last two or three years in marine applications. This means leaks and possibly bearing damage and cavitation (sucking air).

Chemical pumps are magnetically coupled with the shaft and any other metallic parts isolated from the wet end of the pump (inside the volute where the impeller is housed). Magnet coupled pumps last at least 20 years in marine applications with little or no maintenance. They are also more quiet than direct drive pumps as a general rule.

The newest trend in aquarium pumps is modified powerheads such as the Laguna Maxflow, Red Dragon, ATB Flow Star, and the yet to be released Vertex Stratus brushless DC pump. They are energy efficient, saltwater resistant, quiet, low vibration, high pressure, and in the case of the DC models, variable speed. The basic difference with these pumps compared to direct drive and magnet coupled pumps is there is no metallic shaft at all. The impeller is attached to a cylindrical magnet that fits right into the pump motor body. There is a modest ceramic shaft that holds the impeller and magnet together but it’s more for balance and alinement than drive.

Direct drive pumps are prone to leak or suck air but it’s rare to have the seal completely blow apart. The silicone carbide seals on the Sequence pumps are very good quality. They last much longer than ceramic seals. The Pentair site calls their seal “stainless steel” but I think the wording is misleading and they are talking about a seal for a SS shaft and not a SS seal??? This is what the good ones look like.

I pay the extra money for magnet coupled pumps. They pay themselves off in the long run. Panworld and Iwaki pumps are just as noisy as Sequence pumps but their high pressure design yields more overall flow. For example a 290 watt Panworld HD 70 or Iwaki MD 70 series pump (rated at 1750/1500 GPH) will move the same amount of water as a Sequence Dart rated at 3600 GPH @ 160 watts. The Panworld & Iwaki pumps will pump water 39′ high, while the Dart will only pump 12′ high. Sequence has a few pressure pumps like the MantaRay, but it’s 690 watts for 4200 @ 7′ and it’s still direct drive. After 5 years or so you will be seeing cavitation, noisy bearings and maybe even a drip.

Iwaki MX series is good for those who want a strong pump (up to 5 HP) with high pressure, low noise (50-60 dB), and saltwater safe non-metallic magnet coupling. The MX series are designed for industrial use so they have several carbon parts for run-dry protection. The 5 HP pump runs at the same ambient noise as a hammerhead.

There are a few pump maintenance issues that come up. The bearings are sealed so that’s off the list, so that leaves human error, which includes but isn’t limited too saltcreep/spray/drip on the motor, poorly vented cabinets (overheating, dusty fan), sand allowed into the pump, and over dosing calcium. A high calcium level will not cause calcification of hot/warm moving parts in the pump. However, overzealous addition of calcium hydroxide (kalkwasser) and calcium chloride (turbo calcium) will allow excess/free calcium to bind with hot pump parts. The Balling system in particular is bad for this. Proper dosing and/or a calcium reactor will eliminate the need for washing pump parts in vinegar or other weak acids.

I’ve never taken apart an old system, even after 20 years, and found calcification in the pipes. I have however heard of reports of calcification in pipe intakes with extremely high calcium dosing and general alchemy. Hard tube worms and other non-photosynthetic inverts do not attach in high flow pipes or even drain lines to a great extent. You can expect a little bacterial slime in slow moving pipes, but nothing a few on/off cycles of the pump won’t clear.

Calcification is another problem that is isolated to cheaper pumps like the Sequence series. Chemically rated pumps have numerous anti-corrosive features that keep it clean and running smooth. This is the hidden value of Iwaki pumps.

On the subject of heat transfer there is some misinformation out there. Some non-fan cooled pumps like the smaller Panworld, Iwaki, and Poseidon/Velocity pumps are reported to raise the water temp 5°F. This is only true with unvented cabinets. The pump throws off heat and if trapped in the cabinet, it will heat the water. It isn’t a simple heat transfer from the motor to the wet end of the pump. Add some lower cold air intake vents and some upper hot air exhaust vents and an exhaust fan with tight enclosures. The evaporative cooling offered by a fan pointing directly down at the sump will out-cool whatever heat a pump can transfer.

I have never witnessed a long term bulkhead seal degradation. I still have some “brand new”, never used, Rainbow Lifeguard bulkheads and they still feel like the day I got them in 1991 when they came out on the market (I bought hundreds of them so I’m still finding them squirreled away like acorns in my parts boxes in various storage areas). I’ve taken apart hobby tanks and fish warehouses that are over 30 years old and I can’t say that I have seen an EPDM bulkhead gasket go completely hard, crack or leak. I have however seen cheap valve seals leak after only 5-10 years of exposure to saltwater. It’s tempting to buy the $5.00 valves from Lowes when the industrial quality ones are $30, but you get what you pay for. Shop around and find a deal on good ones. Buy a few spares so the size matches up should you do plumbing upgrades down the road. You can always grease rubber parts with silicone grease upon installation or later on down the road as preventative maintenance. Keep in mind, some sleeping dogs should left to lie. A well intentioned turn of a valve union or tightening of a bulkhead can tweak a gasket, washer or “O” ring the wrong way or shift a BH sideways.

It’s really a case to case issue with plumbing and pumps. There are arguments on both sides of the fence and new products are emerging that influence the decision every day. I have been keeping marine fish since 1979 and this is the first year where I’ve seen technology make a significant advance. Most of our gear has changed little since the 1960s. I remember the excitement in 1979 when powerheads came on the market. They really haven’t changed much until the last year with DC options, controllers and larger props. MHL lighting went from 5500K to 20,000K back in the early 1990s, but not much has changed in the past 20 years. Protein skimmer ads have flooded aquarium hobby media for the past 20 years, but they haven’t improved much since the 1960s air driven units in my opinion. External centrifugal pumps still haven’t changed since the 1960s and I would say even earlier if you don’t look at power consumption and size. The apple cart has been flipped, and the aquarium industry is finally ready for technology.

In general I shy away from any form of submersible pump, but the new ones no longer shock you, use markedly less energy, run quieter, vibrate less, don’t spin backwards and stop when the power goes out and don’t appear to have much heat transfer. Now they actually have ports for attaching plumbing instead of a jerry-rigged hose and cable tie combos. The issue of stray current has been resolved with low voltage and DC motors. I’ve been shocked by powerheads more that two dozen times and have seen at least as many melted powerheads that threw some sparks and charred some sumps on their way out. When it comes to fire hazard, I don’t care how cheap they are.

So now … sure, I would use a dedicated powerhead to run individual devices. Trying to daisy chain a protein skimmer, UV, media reactors, and a bypass refugium off of your return pump can become a nightmare. If your water level in the tank rises or your sump level drops the water rethinks its fastest escape route. This wreaks havoc on protein skimmers and fluidized bed media reactors. An all in one pump offers the benefit of having just one cord to plug in instead of an octopus, it saves room in your sump, there is only one (large) intake screen to keep clean, it can be hard piped or at least use heavy duty fittings (instead of a crappy 1/2″ hose on a powerhead that will collapse under its own weight), and you can fine tune flow at the turn of a valve… well five of them (@ $25 ea.). There goes your savings.

There are many factors that can sway you in either direction. I still use a single pump and run my devices in sequence. I don’t use fluidized bed filters and don’t feed the skimmer with the return pump, but I don’t have a problem supplying water to the Ca reactor or sealed canister filters (mechanical, chemical, UV). I find it to be much cleaner and reliable. It also gives me more flexibility in return pump selection as most pumps are too strong for my needs. The cost is often negligible when upsizing to the next pump up.

Some filtration devices can be fed with the closed loop pump. Wave makers such as the Oceansmotions line of products offer an ebb and flow (on/off) cycle or directional change that keeps media filters from clogging and acts as a fluidized bed (media floats up under pressure, then sinks and reclassifies/mixes as the pressure drops in a continuing wave cycle). Running a mechanical filter on a closed loop, or return for that matter, only works if you are using a pressure pump. Because there is zero head pressure, many closed loops use volume pumps instead of pressure units. There still is friction loss and poorly designed manifolds and reducers working against the pump.

Using the same model pump for two closed loops has a distinct benefit in that a third back-up pump is easily swapped in/out. I try to make my plumbing as symmetrical as possible so ins and outs can be reversed to backwash intake strainers and plumbing, and to lay a solid foundation for future improvements (or at least changes).


Mr.Wilson Writes on Power Head Placement

The best powerhead configuration in my opinion is to position one or two at the top of one end panel facing the opposing end where the overflow box is (hopefully). Then position one or two powerheads as close to the bottom as you can get without disturbing the sand too much, at the opposing end (below the overflow box). This will give you that barrel roll or circular flow. It’s about as close to a gyre or laminar flow that you can get with powerheads. Unlike a closed loop, powerheads must suck and blow from the same end so a true gyre is impossible. The benefit of having half of the powerheads at the surface is you get more ripples and subsequent shimmer effect with the lighting.

With this kind of flow dynamic, it would be wise to set up your sump return line(s) to enter at the end where the overflow box and where the powerheads are near the bottom. Point the return line(s) straight down a few inches below the surface to continue the circular flow dynamic. The water coming from the sump will get picked up by the lower powerheads and get shot across the bottom of the tank. The water takes the longest trip possible before returning to the sump to be filtered again.

Some powerheads have a surge pattern whereby the pump cycles on and off in short bursts continually. If you can get the powerheads at the opposite end to run on a reverse cycle, and you time it right, the powerheads can catch a wave and continue it. Vortechs have a communication system, but unfortunately they are programmed to cycle on and off at the same time instead of a preferred staggered pattern.

Aiming powerheads directly at the rock structure will accumulate detritus as it forces particles (POC) into the rocks. Moving water from the bottom to the surface is the most efficient flow for gas exchange and climate control, but this is a challenge for most powerheads. Burying powerheads in rockwork makes it difficult to service the impellers and keep the intakes clean. Chaotic flow has some benefits, as it encourages corals to grow in all directions due to even food dispersion, but chaotic eventually forms a pattern and detritus finds dead spots to settle in. Chaotic flow also creates resistance/friction that diminishes opposing flow.

Laminar flow (gyre) creates momentum and kinetic energy/inertia. The whole idea of moving water in one direction, be it circular or linear, is the wave of the future (pun intended). Think of it like putting your hand in a bucket of water and quickly mixing the water clockwise (or counter) for 5 seconds. When you stop, the water continues to travel in a circular motion for quite some time. There is minimal friction loss as the flow doesn’t crash into obstacles such as opposing flow, rock structures, or viewing panels.

In some cases there is a benefit to extending the intake of the powerhead to the bottom of the tank, assuming it is mounted at or near the top. This simple pipe will draw less oxygenated water from the bottom and deliver it to the top where the air/water interface can re-oxygenate it and off-gas nitrogen and CO2. The intake extension also creates a passive circular flow as water is propelled across the surface and drops down to be sucked up again. I find that powerhead intake screens are undersized in length, diameter and hole size so they plug quickly and restrict flow. A weekly scrub with a toothbrush will rectify this, but access can be difficult. Adding a larger intake screen at the bottom of an extension pipe or simply drilling holes in the pipe will spread out the suction and minimize the need to service the intakes.


Mr.Wilson Writes on Using Teflon Tape

Set-ups with 100% rigid pipe are almost impossible to seal. The valves leak no matter how tight you torque them. The bulkheads slip and bend to the point of leaking. It also isn’t safe. If you lean on a pipe, you are leaning on the tank, sump and plumbing joints. If you are using Tigerflex/spaflex hose use Weld-on #795 flexible PVC glue as it can take some flex without cracking. I also use lots of primer. The clear primer is getting harder to find. The purple stuff is considered “professional” because it is used to assure you didn’t miss a spot and more importantly so an inspector can see that a pipe fitter didn’t get lazy and skip a step (against building code). We don’t have inspectors and they can tell by the floor, my tool box, my hands and shoes that I used the purple primer. If you are really anal about how your plumbing looks you can use acetone on a clean cloth to remove the lettering on the pipes.

I can’t speak for pool installers, but we do use the same fittings and I can guarantee they will leak if you don’t use teflon tape. Brass fittings don’t require teflon tape as it seals itself due to its soft nature, but I use the tape so it’s easier to remove it later. Of course you don’t use brass fittings in the tank, but they do show up on CO2 regulators, etc.

For about 10 years I used the thicker pink teflon tape (for metal gas pipes) instead of the white stuff (for plastic water pipes), on the advice of an older and wiser aquarist. The idea is that it fills the gaps without having to wrap it more than two times around and with better consistency. I don’t know if they changed the material they used or if my luck just ran out, but I started getting leaks with the pink tape. I switched back to the white a few years back and I’m sticking with it, but there has to be a better way. Most people will tell you they never get leaks. Remember to add four or five strokes to their golf score.

For those who are completely new at this, the tape needs to be wrapped three to four times around the fitting starting at the end and working toward the base where the thread ends and the PVC adapter begins. You need to wrap the thread over and away from you (clockwise) if the part is in your left hand, or under and toward you (clockwise) if the part is in your right hand. It is important to turn clockwise or it will peel off (unravel) when you tighten it into the female thread. I leave the tape thin (two wraps) at the end where the thread starts to mesh with its female counterpart, and I use my thumbnail to cut a thread in the tape. This makes it easier to get the thread started and avoid cross threading. Tighten it as far as it goes by hand and then spin it one revolution with a wrench. This is where you have to use your built-in torque wrench powers to establish how tight is watertight without cracking the female part. These splits can be minute so you may not notice until it gets the wet test. A stressed/over-tightened fitting can also split days or weeks later when you aren’t around. Some industrial fittings have metal rings around the female to assure that the tapered male thread doesn’t wedge it open. As I mentioned before, a small length of flex/spa hose will relieve stress put on pumps, valves, unions, and tanks. People get over zealous wrestling with pumps and valves and forget that there is a delicate glass tank attached to those bulkheads.

I also mentioned that some vendors don’t get the thread exactly right. When plastic fittings are made they are heated then cooled. If the cooling process is too long or too short it will affect the final size of the fitting (shrinkage rate). I often find batches of slip and threaded parts that simply do not fit. I have also found certain parts that are too thin and weak. For example, George Fischer 3/4″ female adapters (FPT x socket) which is female pipe thread by female slip fit, frequently split open with even hand tightening. When this happens I assume it’s a bad mold and move to another vendor like Spears or Dura. Valves are another sensitive area; buy premium valves with a single or double union so you can take it apart later without losing prime or draining the tank or sump.

I have considered trying plumbers paste for threads. Apparently it’s “foolproof”. The problem is it limits your ability to take the part off which defeats the point of threaded parts. 99% of leaks are from threaded parts. In Europe they still use horse hair and “dope” (sealing compound/paste).

I still lightly tape (1.5 revolutions) threaded parts in the tank that aren’t under pressure. It makes it easier to take them apart after calcification and over-tightening. Teflon tape is a lubricant as well as a sealant. Do not silicone PVC parts, as it will not bond properly and interfere with the the thread seat. If you accidentally loosen the part, the silicone seal is compromised and a leak will form.

I’m still learning after 23 years. Last year I discovered what the arrow on the valve is referring to. It sounds easy… the arrow indicates the direction of flow right? Wrong! The arrow denotes the direction that the water can safely travel when you are servicing the pump without blowing out the ball in the valve. The valve is designed to be disassembled for service, namely “ball cleaning”. The ball pops out one of the two sides but not the other. This is referred to as a “checked ball”. With most premium valves the valve handle works like a key to open the valve housing. Pull the valve handle off and it has two protrusions on the inside like a key tool. Discount valves are not “checked” on either side so if you shut the valve off at 90 degrees then open one of the unions (threaded couplings), the ball will come flying out along with the contents of your aquarium. Well, I learned all that stuff the hard way years ago, but I didn’t learn the arrow code until last year. The arrow should point toward the pump for the “in” (influent) as well as the “out” (effluent). This assures that the water pressure can push the direction of the arrow without blowing your balls off. Some non-union valves have an arrow. This arrow does in fact indicate the direction of the water during normal operation. I think the plumbers design this stuff for job security

Another trick is to check the floor for spare “O” rings. They have a tendency to fall out especially when you are frantically taking the pump on and off. A little silicone grease will help them stay seated, slippery and sealed. Do not over-tighten valves and unions. Hand tight is all they need.

Bulkheads get the hand tight plus one turn rule, but be careful with the black PVC ones, they can crack and strip threads with even hand tightening. The original Rainbow Lifeguard (now Pentair) black PVC bulkheads were very durable. You could jump up and down on a 10′ cheater bar and you couldn’t over-wrench them. Companies started knocking them off in China and now you can’t tell what you have. I go through a box of them at my supplier and test the flynut for play. If the flynut jiggles too much (sloppy thread) then I know it will strip and fail. You also get batches where the nut doesn’t quite match the body of another batch. You discover this when you have ten BHs on set in the tank and a handful of flynuts that you need to match up like lost keys. Another problem is with the combo slip/thread they use on the wet side of some BHs. It is neither a slip, nor a thread so it’s useless. The translucent blue BHs are weak and break easily. You guys don’t even want to know how I know all this. Many people are moving to schedule 80 (heavy duty) industrial BHs even though they cost four times more and some tank manufacturers don’t have the glass drills for them. The best black BHs are the ones with a white flynut with the stress notches cut in them. The white Hayward pool BHs are still tough as nails as well as fool and leak proof. The double-sided gasket seal and cardboard flynut slider assures a good seal without pinching or shifting the gaskets. Going with a larger 1.5″ BH gives you more flexibility in the future for changes. You never know when that 3/4″ return line will need to become a 1.5″ closed loop intake. It’s easy to reduce a 1.5″ hole down to 3/4″ but the hole isn’t getting any bigger if you want the reverse.

Here is a handy pipe flow calculator.


Mr.Wilson Writes on Aquarium Wiring

Try to use independent GFCIs so one failure doesn’t take down the whole system. It’s a tempting shortcut to daisy chain two or three outlets off of a GFCI to save some money, but this exposes you to more peril.

Some GFCIs have very sensitive reset/test buttons. AC adapters can put pressure on these switches and cause a false trip. Add a 6″ mini grounded extension cord with an illuminated base plug. This will let you orient your AC adapter any direction you want without blocking the other outlets or tripping the GFCI. The lighted plug makes it clear if the outlet is on. GFCIs have a tiny green light but they are difficult to see in daylight, aquarium light, or when blocked by plugs & wires.

Use a drip loop on any cords that run above the outlet. A drip loop is a loop tied in the cord with a cable tie to provide a low point for water to drip off so it doesn’t run straight down the cord and into the outlet.

Strap powerbars down to the aquarium stand legs with cable ties so they can’t fall in the sump or become dislodged when you yank the cords. Labeling the cords and or outlets save you some headache wile looking at the octopus of wires.

Try to run the return pump on a separate circuit from the closed loop or powerheads. This way you always have water movement if just one circuit trips.

Outdoor timers give you added humidity resistance and splash resilience. I use battery backed up digital ones with remote controls so the aquarist doesn’t have to even know where the timer is, much less start pushing buttons randomly.

Disable any wall switches that affect the tank. You never know when the cleaning lady will turn off your return pump accidentally.

Use cable ties and wire covers to bundle up and organize wiring. Make it so a device can be unplugged and removed without tearing the place apart. I use plastic C clips to affix wires to the wall, but I leave the C open (like a U) so the wire can be removed easily.

Use a titanium grounding probe in the display tank and the sump.

Set up a back-up system with a deep charge marine battery and auto activate/charging system. Something like this.


Mr.Wilson Writes on Mangroves

Mangroves are not fast growers so they do not directly export significant amounts of nutrients or heavy metals, but they do foster the growth of microbes on their root mass that consume the bad stuff. Like the Miracle Mud, they also harbour lots of water polishing benthic detrivores.

The most interesting feature of mangrove trees is the tangled web of roots. In order to get your mangroves to grow “legs” like this, you need to elevate them 4-6″ every month or so. This practice simulates the ebb and flow of tidal waters and or heavy rains in mangrove swamps. In nature, the water level drops and the mangrove tree stretches its roots deeper into the water. You will see a change in the colour and texture of the roots as it adapts to the change in water level. The lower root mass is green and smooth and it is adapted to being submerged, while the upper root mass is brown and rough more like traditional bark. The upper “air roots” are more for structure than water collection.

Mangrove trees don’t actually require salt water and do quite well in freshwater and soil. Mangroves are able to extract freshwater from saltwater and expel the salt through their leaves. In nature, morning dew and rain washes the salty residue away, but in a home aquarium you need to have one of your staff wipe them with a wet cloth by hand.

Mangrove trees have a high demand for magnesium, so they should be planted in dolomite (calcium magnesium chloride) which is available at your local farm supply store. You can add some dolomite to your calcium reactor (if you decide to get one) to buffer magnesium, which stabilizes calcium supplementation.

They actually grow faster in soil with freshwater. If you want to jumpstart a mangrove filter, grow them in pots in soil outside in natural sunlight for a few months first. A friend of mine has had about 20 mangroves in a deep sand bed filter for over 20 years now. They are only 2′ tall with few leaves. He’s growing them under MHL, but they don’t do much.

DSB’s and mangrove filters don’t have a good record for success stories, but they certainly don’t hurt or cost much to set-up or operate. I actually use remote deep sand beds (RDSB), mangroves and do water changes, despite the lack of empirical data showing that these make much of a difference.

Most of the methods we employ are not miracle cures, but together they are a catalyst to success. The solution to optimum water quality lies in baby steps, not in a magic bullet. Mangroves are one of those small steps. Julian Sprung wrote a small booklet on mangroves if anyone is interested in reading more about them.

There are three types of Mangroves from different parts of the world: black, white, and red. I believe the black are from Asia.

Mangrove pods are considered seeds and therefore do not require a phytosanitary certificate and inspection as would a plant. You would have to take them out of the soil for them to qualify. Having said that, they may delay you at the Canada/USA border as you try to explain the difference between a pod and a plant.

While mangroves do not add oxygen to the water, they do however add it to your fishroom and more importantly, they convert CO2 to O2. If you have a bunch of fish guys over who never stop talking, the pH in the tank will drop considerably due to the increase in CO2.

Terrestrial plants like mangroves are a perfect natural remedy for this problem. They also strip the air of harmful VOC’s that might otherwise make it into your system or source water container.

The white, black, and red varieties of mangrove tree all occur in Florida and they are all appropriate for aquaria. The three varieties are fairly similar with only a few minor root system (breathing) and leaf systems (salt expelling) differences.

The ratio for a tank under 30 gallons should be 1 per gallon, and for larger tanks you can get away with one per two gallons. Julian Sprung recommends 1 mangrove pod for every two gallons. That should help you decide how many you need.

There are a few mangrove tree farms in Florida. They can legally sell pods and trees over 3′ tall, but anything in between is protected by Fish & Wildlife Services. The nursery trees are a 3′ straight stick with about six leaves on the top. You have to look really close to tell the difference between the three colour varieties.

Starting with pods and varying the rooting depth will make a nice tangle of “legs/knees”. Trimming the top to like a bonsai will manipulate growth hormones and cause the tree to send out new branches.

Each plant will grow one new leaf per month and the amount of nutrient uptake is similar to that of macro algae. You can dry the leaves and weigh them to compare the export yield to the dry weight of a month of Chaetomorpha or Gracilaria growth which will be closer to a bucket full. The dry export weight of mangroves is not only less than macro algae, it also takes up a larger footprint and uses more resources (spraying and lighting). Macro algae also offer the added benefit of converting CO2 into O2 in the water. Macro algae refugia should be run on a reverse photoperiod to counter coral respiration at night so the pH doesn’t drop. Mangrove tanks should be run on a daytime photoperiod so they can convert atmospheric CO2 into O2.

You have to remember that you are working with a closed system where the air in the room is independent of outside atmospheric air and the water in the tank doesn’t have the massive expanse of the ocean to balance the CO2 and O2 levels. CO2 can become carbonic acid and like any acid, it lowers the pH of the tank water, particularly at night when photosynthesis reverses the process and O2 is converted into CO2. A nightly pH drop from 8.2 to 7.8 is not uncommon, but a reverse photoperiod refugium full of macro algae will balance this out. Mangroves, or any terrestrial plant for that matter, intake CO2 through the stomata pores on the underside of the leaves. This is a process that is carried out above the water, so it has no impact on the gas exchange in the system.

It would take a substantial number of mangroves to have a significant impact on the ambient air quality. Common house plants like Pathos and spider plants are boring but they are the most efficient at removing VOC’s from the air. Gas exchange will be greater with a more substantial ficus tree or fast growing philodendron.

I view mangroves as primarily for aesthetics with some value as a microbial site. The little critters that grow on the mangrove can just as easily be grown on rock or eggcrate, but mangroves are more fun. If you want to look into alternative methods of nutrient export, sea grass is fast growing, efficient and equally as cool looking. There are some nice sea grass fish and inverts (Bangai Cardinals, pipefish, and filefish) and you get the water flow to make them sway. The catch is they are hard to find and don’t transplant well as they need the long root system to be intact.

It’s a common misconception that the roots (holdfast) of single celled algae draw in nutrients from the substrate. Sea grasses do however uptake nutrients through a root system just as terrestrial plants do. The practice of placing nutrient-rich mud under sand for the roots to “get nutrients” is erroneous. Macro-algae and mangroves are being implemented to reduce excess nutrients, so any efforts to “feed” them are counterproductive.

Black mangroves are unique in that they develop a “snorkel” system whereby the air roots become soft and spongy with pores to supply oxygen to the roots if they are growing in anaerobic (oxygen-poor) conditions.

If you grow mangroves without any substrate the root system will continue to grow, stealing energy from the rest of the plant above water. Mangroves, like any plant, need to be potted in a suitable sized pot so root growth can be limited so more leaves and branches can develop. The size of the plant is dictated by the size of the root system. If you restrict the roots’ growing room too much the plant will be stunted.

Mangroves should be grown with 6500K metal halide lighting. This will provide the intensity and coverage they need. 175 watts will suffice, unless you are growing a lot of them with a higher wattage (250 or 400 watt) metal halide fixture mounted higher above the trees.

Mangroves don’t require salt to grow and will actually do better in soil with freshwater. I like to grow them in soil outdoors in the summer. Mangroves cannot compete with terrestrial plants surrounding the estuaries (mangrove swamps) they are found in possibly due to their slow growth rate. They have evolved to be tolerant to saltwater so they can live in marine environments where there is no competition.

Mangroves excrete salt through their leaves so they need to be sprayed with freshwater daily and perhaps wiped. Nature takes care of this job with morning dew and rain. A daily spray will also humidify the air, as they come from a humid environment. Dry air, particularly in our homes during winter, dries out the leaves. Mangrove leaves are shiny due to a protective coating that seals in humidity. A dry room will cause the mangrove to lose some of the water that it works so hard to extract from saltwater.

Mangroves grown in saltwater use magnesium to force/pump sodium salts out through their leaves. If grown in freshwater or soil, they do not require magnesium. Bioavailable magnesium can be supplied via dolomite gravel which is calcium magnesium carbonate. As the chemical name would suggest, it adds the three main elements that reefs require supplementing – calcium, magnesium and carbonates (KH). Localized acidity caused by bacteria in the dolomite will slowly dissolve it and make it bioavailable to the tree. Otherwise having a magnesium level of 1300-1500 in the system water is sufficient. If they don’t get enough magnesium they experience yellow or shrivelled leaves. Growth of the plant and subsequent nutrient uptake will be limited if the magnesium level drops significantly.

If you want to experiment you could add pelletized sulfur to the dolomite for a passive sulfur denitrification filter. Sulfur filters/reactors encourage an acidic environment by feeding denitrifying bacteria. This would create a passive calcium reactor, slightly raise carbonate hardness (KH/alkalinity), and moderately raise magnesium. The added bonus is denitrification (lowering nitrate). You can read up on sulfur denitrification here. I’m suggesting a scaled down version of the reactors discussed in the thread so dissolution rates will be only marginal in comparison. The pH will be nowhere near as low as with a calcium reactor (7.7 vs. 6.5 pH). You need to use a 99.9% pure sulfur pellet and not the 90% pure sulfur pellets used in agriculture that are designed to dissolve quickly. The agriculture pellets turn to mush quickly. The effluent (out going) water from the mangrove tank should pass through a granular ferric oxide (GFO) reactor as the iron will react with any residual hydrogen sulfide that forms, converting it to a less toxic form of sulfur.

The amount of nitrogen and phosphorus in reef aquariums is more than enough to supply the mangrove with what it requires for growth. One of the chief limiting factors that you will experience with mangroves grown in a reef system is carbon dioxide (CO2). If you really wanted to encourage growth, you could add a second line from your CO2 tank (for your calcium reactor) and put it on a timer and solenoid to dose CO2 every few hours during the day. Mangroves have pores on the undersides of the leaves called stomata that breath in CO2 and breath out O2 during photosynthesis. Aiming a circulation fan at the mangroves will also provide more CO2 to the leaves. A classroom full of kids is more than enough CO2. Even urban (high) vs. suburban (moderate) vs. rural (low) ambient CO2 levels will affect how well the plant can grow.

Most plants require well oxygenated soil or substrate, but mangroves have evolved in oxygen-poor (anaerobic) soil so they don’t need water movement through the root zone. Black mangroves in particular have snorkel roots that are spongy so they can draw oxygen from the surface and deliver it to the root mass. A flow-through substrate with more oxygen (aeroponics) will not provide any benefit to mangroves.

The bark surface above the water is rough and brown, while below the surface it is shiny and bright green. You can lower the water level or raise the tree/pod to simulate a dry season or low tide. By doing this, you encourage the tree to send out prop roots (air roots) as the roots stretch down for more water. Red mangroves have the nicest prop roots. If you leave the mangroves in one static position, they will not develop the prop roots and character they are famous for.

You can trim mangrove trees like bonsai and even bend them with wire to shape them. By pinching off the top leaves occasionally you send growth hormones down to the lower levels of the pod/tree so new branches and leaves start. Bending the top of the plant down a few inches also transfers growth hormones from the top to the lower parts of the plant. This adds new growth to lower areas without compromising (cutting) the top.

Mangroves are slow growers even in the best conditions. You can expect one or two leaves a month growth per plant which will yield a modest dry weight in nutrient uptake. Mangroves do not add oxygen to the water as their photosynthesis is independent of what goes on underwater.

You could add some anableps, archer fish, mudskippers, cardinals or fiddler crabs to complete a mangrove estuary theme. An ebb and flow system that raises and lowers the water level in a cycle would also be interesting. If you were short on space you could grow a vertical wall of mangroves but you would have to use a slow flow system to minimize salt creep.

I forgot to mention, Miracle Mud would work fine as a planting media for the mangroves. Of all the products readily available, it’s the closest to what they would be found in their natural environment.


Mr.Wilson Writes on Aiptasia Anemones

Peppermint shrimp work well, but best in a group. In small numbers they are too shy, and hide.

I find copperband butterflies to be the most efficient. There is a blenny from the Atlantic Ocean that eats them, and of course burgia nudibranchs. We have a filefish that eats aiptasia but we haven’t decided if it is reef safe (enough) yet. Most people have no problems with them and the few that experience coral picking may not be feeding enough (?). We are still thinking about our Cuban and Spanish Hogfish as well. They are known to eat small shrimp, crabs and bully smaller fish, but it is a large tank. Having said that, it is a large tank to try to catch them out of. You can break some rules with larger tanks, but in the end the fish call the shots.

Believe it or not, putting rock in a microwave for 30 seconds works. It will kill anything that is full of water like sponges, tunicates etc., crabs, shrimp, but coralline algae is fine though.

I see no benefit in sterilizing live rock with chemicals or keeping it in the dark because aiptasia are more likely to enter the tank with coral than rock.

In my opinion chemical dosing to remove aiptasia doesn’t work. You could mix some calcium hydroxide in with the EPO Putty to make it a poison as well as a physical barrier. This would solve the problem of trying to jab them with a needle. The physical barrier will deter reproduction which isn’t as common as some report.

For those of you who don’t have experience with aiptasia or majano anemones (I have been very lucky in this area) a common practice of removal is to poison them. The safest way to poison anything is to give it too much of a good thing, that way it is safe once diluted in the tank. You can use alkaline (high pH) or acid (low pH) chemicals that will quickly neutralize once it drifts away from the anemone such as salt, calcium hydroxide, sodium hydroxide, calcium chloride, acid (muriatic, vinegar etc.). You can also use oxidizing agents like iodine, peroxide, and potassium permanganate. In the old days some people roughed up a copper wire with sandpaper and jabbed the anemones in the hopes of dislodging copper fillings in them. Squirting a small amount of copper sulphate would have been more effective but why use a true poison when there are lots of reef safe things you can overdose them with

The pest anemone may turn up in a different hole in the rock. Live rock has far more passage ways than we give it credit for. Continuing to plug holes as they arise will eventually solve the problem and adding chemicals to the EPO Putty will help.

What I like about the putty solution is it’s quick, easy and cheap. A roving aiptasia eater is a better solution for a tank that is plagued with a big outbreak.


Mr.Wilson Writes on Skimming Part-time

The skimmer takes out carbon (TOC) and bacteria. Both of these are food sources for corals and fish. Many skimmerless tanks have better polyp extension and growth rates. The problem is, these tanks can also have yellow water, turbidity (cloudiness) and nuisance algae problems. I have even had phytoplankton blooms (green water) in skimmerless reef tanks. Until we find a better way, a compromise between a natural and mechanical system is the safe route. Shutting the skimmer off half of the time is a good place to start. If conditions get better or worse, you know which direction to go; if they stay the same, it still confirms the limitation of protein skimming. Then you start to think if it was really worth it to upgrade your skimmer the last two times I don’t see a benefit in any schedule other than 12 hrs on, 12 hrs off.

So now that we have decided how long to shut it down for (12 hrs/day), we need to decide on the best time. The fish and corals are most active during the day during photosynthesis, and at night the corals open their feeding tentacles to collect the plankton that come out when the lights go out. Shutting the skimmer off at night seems to be the smart move, and if it influences the flow in the tank to slow down, even better.

One way of achieving the shut down is to have the pump on a timer. This is the quick and easy way, but the preferred method is a variable flow device (VFD) to slow down the pump to allow the skimmer to “simmer” so it can still function if there is a spawning event or call for skimming. A VFD also allows you to ramp up to wet skimming a few times a day to keep the skimmer neck clean, grab some stubborn semi-hydrophobic proteins and do a passive water change (just keep an eye on salinity).

Pumps with flow control are expensive. You may be able to set up a cheaper solenoid that restricts the air line feeding the needle wheel. You will have to get creative and rig it to shut only part way at night so some air can still bleed in. Drilling a hole in the solenoid may work, but I’m not sure how you will “tune” it. Skimmers with two or more needle wheel pumps make it easy because you just need to keep one pump on and put the rest of them to sleep at night.

At this point in time you are probably asking yourself, “Then why not just turn down the skimmer and run it 24/7?” or even, “Why not use an undersized or cheapo skimmer and put the money elsewhere in the system?” The key here is having skimmer reliability, and you simply won’t get that with the cheapo skimmers on the market. When they go “on strike” or flood the collection cup, when the air intake crystallizes, or the water level varies, or the pump disconnects, or stops entirely, you don’t have a skimmer, and you can’t predict when this will happen. With a well designed skimmer, you buy peace of mind and in the long run, you pay less because you buy just one skimmer. In other words, do it right the first time, and do it once. The other option of running a premium skimmer on a slow and steady, conservative setting is a “neither here nor there” solution. You end up with the worst of both worlds because the skimmer neck will slow down efficiency with skimmate (muck) build-up in the neck, which you will have to clean manually. It also doesn’t achieve our goal of leaving the tank “natural” during the nightly plankton swim.

Shutting ozone down at night is a parallel issue. You can put your ozonizer on the same timer as your needle wheel pump. Your ORP controller may have a day and night setting. UV sterilizers may be worth shutting down at night as well, but don’t start unplugging everything at once; ease into a night mode one device at a time over a few weeks. This way there is no shock to the system and you will have a better handle on the repercussions of each device.

While we are on the subject, there may be merit in shutting the refugium off during its night/dark phase. During the “day” algae utilizes/removes nutrients (nitrate, phosphate, heavy metals etc.) during photosynthesis (cellular respiration). The algae in your refugium converts “bad” CO2 into “good” O2; however, during the “night” (photorespiration) algae converts O2 into CO2 thus lowering the pH (liquid CO2 is carbonic acid, and like any acid it lowers pH). The same pH shift and gas exchange occurs within your corals carried out by symbiotic algae (zooxanthellae). Many people run their refugium on a reverse photo-period (refugium illuminated at night and kept dark during the day) to balance the pH and photosynthetic processes of the refugium and display. During the day, the zooxanthellae are generating O2 for the refugium while consuming the CO2 the refugium is producing, and the reverse process at night. At night the algae in the refugium leaks out some of its nutrient catch. If you take the refugium off-line during its night/dark phase, it assures that the leaked nutrients don’t make it to the display tank. When the lights come back on over the refugium (which should have 16 hrs of light and 8 hrs of darkness) the algae will re-absorb the lost nutrients.

Peter’s tank is much more than a pretty picture of a reef. We intend to fully test what each and every piece of equipment can achieve, source out its limitations, and find solutions for optimum performance. We have adequate testing equipment and protocols to evaluate the best practices we have been talking about throughout the thread, but the best part about working with Peter isn’t the budget or resources, but his willingness to admit when we are wrong and scrap the conventions of modern reefkeeping. Simple details like taking a skimmer or refugium off-line at night may prove to be invaluable practices that anyone can do at little or no cost. It’s easy to buy the most expensive skimmer on the market, but there is a lot more to it than dropping it into the sump and plugging it in.


Mr.Wilson Writes on Algal Turf Scrubbers

ATS (algal turf scrubbers) have a bad reputation due to the wide definition and sometimes poor application of the method.

What we now call a refugium, is an algal turf scrubber of sorts and they do work well. In my opinion the limiting factor is the great depth at which the algae is allowed to “ball up”. The lower levels don’t get light and subsequently die off leaving the nutrients they have trapped. A shallow trough (4-6″ deep) minimizes shadowing and optimizes growing conditions.

Another issue is algae selection. Most varieties of algae have around the same nutrient uptake. Some are faster growing than others, but this can come at the cost of stability. Caulerpa is faster growing than Chaetomorpha or gracilaria, but it can die off with sexual reproduction if the photoperiod and water quality ranges, as these are cues of season changes in the wild. With a 12-16 hour steady photo period, it is unlikely that caulerpa will ever reproduce sexually. Turf, hair and cyanobacteria are pest algae and should not be used for an ATS. They can easily find there way into the display, they add yellow pigmented tannins to the water, and they “bleed” when you harvest (cut) them. Nutrients and algae tissue will leak out into your system and cause nuisance algae blooms. Also keep in mind that algae release (allelopathic) chemicals that may restrict the growth of invertebrates so algae selection is important. Chaetomorpha is slow growing in comparison to caulerpa but with high intensity lighting it is more than enough. We are also growing sargassum grass just because it cropped up in he tank one day. We harvest a large quantity of Chaeto every week and along with it quite a bit of phosphate, nitrate and heavy metals.

Another poor design is vertical panels as the cause the algae to tear and fall off. They also cause salt creep, noise, and odours. Often a light is placed close to the vertical panel with questionable wiring practices.

During the day, algae convert CO2 into oxygen during photosynthesis, and at night they convert O2 into CO2 during respiration. During the day they take nutrients out of the water, while at night they release a portion of them. A good ATS design would take the unit offline during the night/dark period. In our case, the refugium is fed by the protein skimmer throughput/feed. Once the system has matured, we will shut the skimmer down at night by putting the feed pump on the same outlet/timer as the refugium light. Shutting the skimmer off at night helps restore bacteria levels, allows plankton to do their nightly swim in peace (instead of pieces), and takes the refugium offline so the chaetomorpha doesn’t leach nutrients or lower the pH (CO2 = carbonic acid).

We are using plasma lighting for the refugium to “supercharge” it. We also have 40 gallons of refugium/ATS on the two walls where our mangroves are planted. Mangroves don’t impact pH as their leaves are above water so we will run them 24/7.


Mr.Wilson Writes on Keeping Gorgonians

The basic guidelines for keeping gorgonians are:

1) Never take them out of the water and expose them to air. If they are, shake the bubbles off so the tissue isn’t damaged.

2) Try to buy ones with brown polyps as they are photosynthetic. The white or brightly coloured polyp gorgonians are non-photosynthetic.

3) Feed them 50-150 micron food at least twice per day, especially if you are keeping non-photosynthetic varieties.

4) Gorgonians from the Caribbean are a little more hardy than their Indo Pacific cousins.

5) Try not to cover the base with glue or substrate as this stresses the gorgonian.

6) Give them moderate flow, not too strong, not too weak.

7) Orient them in a position where they can readily collect food. In other words, have the food travel through the wide “front” rather than the narrow “side” of it.

8) They are tall so they should be placed in the background.

9) They grow quickly so leave room at the top of the reef for growth.

10) Cut off dead branches to deter algae growth.



Mr.Wilson Writes on Cryptocaryon irritans

Quarantine is not 100% effective at eradicating many varieties of pathogens, including Cryptocaryon. There are dormant cells that can reappear out of nowhere years later, and there are secondary invertebrate hosts that can also introduce the parasite to the display. Some LFSs keep fish in their coral systems, further increasing the likelihood of disease transmission. We dip our corals in iodine and pine & lemon oil (Revive), and isolate some corals for a few days for closer inspection, but there are always cracks in our system that parasites can slip through (literally).

Our Blue tang gets crypt on and off, never more than 12 cysts at a time, and this is normal reef behavior. Parasites are part of the reef, and only deserve the name when their population goes unchecked.

It is paramount (IMHO) that you stock the display with a rich variety of parasite pickers. A natural or captive reef simply can’t function without them. They will not work miracles, but they will avert many looming disasters. Parasites are not limited to fish hosts. We picked a lot of our wrasse based on their appetite for parasitic snails (pyramid snails that eat clams), and flatworms. We have the following parasite eaters:

200 peppermint shrimp
5 cleaner shrimp
3 fire shrimp
4 coral banded shrimp
2 mandarin goby
numerous wrasse

One problem with parasite eating fish is poor longevity in some species (Labroides sps. specifically). Many wrasse and angelfish are parasite pickers as juveniles, then shift their diet as they mature to invertebrates that might include some of your prize specimens.

Good diet is also very important, but I find that many people pat themselves on the back for shoveling in lots of food and ignore the other disciplines. A large tank certainly helps put some distance between parasite and host. Reinfection at the end of the parasite’s life cycle is less certain, but still an issue. Fish to fish transmission is a problem with overstocked tanks.

You really have to eliminate as many stress factors as possible to help the fish maintain a strong immune system. More important than quantity of food, is quality. Many omnivores don’t get the algae they need, and some foods that are weak in nutritional value, such as adult brine shrimp, act more as filler than nutrition. The nutrition topic is too broad to fit into this post, so I will leave it at that.

Temperature swings are another major trigger. It isn’t the extremes, but the swing that causes stress and cues reproduction. We are having some temperature stability issues. The ambient room temperature is unstable so the display tank reflects this. Large homes are a lot harder to maintain with multiple furnaces, air conditioning units, floor heaters and their respective thermostats. Peter’s wife Judy likes to open the windows at night so there is a whole other microclimate to work around. The idea is to find where the tank would naturally settle with ambient room temperature, then set up a cost effective system of stabilizing that temperature. It is easier to heat than to cool, but you also have to work at the centre of the safety range and predict the trends if something goes wrong. Will it tend to get too hot or too cold?

There are a few semi-reef-safe treatments such as chloroquine and metronidazole, but I would advise against their use in a well stocked reef tank. You can make a gel food with agar agar which is available in most grocery stores (however buried). Simply soaking food in Chloroquine will suffice. You can also soak food in metronidazole as an ich/protozoan treatment and finish off with neomycin for secondary bacterial infections onset from cyst attachment. I would dose the former two drugs for a month and the later for one week. I use 10 mg/l for three treatments, every second day. AP makes a line of medicated gel foods called Gel Tek. We have some neomycin gel on hand at Peter’s. You can also add powdered medications to off the shelf gel food. I would start at 250mg/feeding.

Just make sure you aren’t training your fish not to eat, as it’s like the old cod liver oil in the jam trick. Now that there are no cod left in the ocean, kids no longer need to worry.

In some cases it is easier to catch the fish out for treatment, and in others it makes more sense to move the corals out and treat the whole display. A good fish trap like the one from Aqua-medic can help you target certain fish for removal. We strategically added fish that were not prone to ich (wrasse, gobies, blennies, anthias) first, then added tangs and angels 6 months later. These are also aggressive fish that should be added last to give the little guys a chance to get settled in. If the QT is thorough and overall aquarium conditions are good, then crytocaryon will not cause fatalities.