Saltcorner
By Bob Goemans
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Bob Goemans corresponds with Kurt Oehlberg

Kurt Oehlberg writes...

Hi Bob,

I am a long-time marine/reef hobbyist and avid FAMA reader (and "Sand Mail" of course). I am exploring the possibility of a move to a new home which would be an excellent excuse for me to re-create my systems (on a significantly larger scale of course). And as I consider my options I would love to gain the benefit of your experience with regard to a couple of questions.

Background: Over the last few months I have waged a continuing struggle with parasitic infections (crypt or oodinium) to the current inhabitants of my existing 200 gallon system and have ultimately had to resort to removing the corals (mostly SPS) to a separate system and treat the main display tank with a copper-based treatment for the recommended multiple treatments over a 2 week period. While I am quite aware of copper's lethality to inverts, my love for, and the high value of the many angels (conspicillatus, septentrionalis, goldflake and others, as well as other residents) that I have kept for many years has ultimately caused me to react in their defense. Other "reef-safe" medications have proved of little, if any, value. I am pleased to say my prized specimens are once again fat, happy and "spotless". I had previously copper-treated the system some 4 months back, achieved the same result (i.e. fish all saved and clear, and system run with copper in for 2 to 3 weeks to take care of remaining to-be-hatched flagellates) only to have the infestation recently re-appear. I know you can never really be rid of all parasites, and I do run relatively high wattage UV sterilization (25W on one return and 40W on the other) continuously after removing the copper with Poly-Bio pads and doing significant water changes, so I was disheartened to see the return of the plague. I recognize there are a host of water quality issues I am not giving you, save to say I am a very familiar with the parameters necessary for my system to thrive, and for many years it had done so. If you care to comment on my above described fight with ick, I'm all ears (or eyes with e-mail). I will obviously observe appropriate pre-treating/quarantine measures before releasing them into their new larger home.

Here is my First Question(s):

I know the live rock and sand substrate in the treated system absorbs some copper, which leaches back into the system over time. How long does it take for this to occur, or alternatively, is there some method of treating this rock during the tear-down of the main system, if I were to use it along with new live rock, to be reassembled in a new and bigger system I am contemplating given the move? While I recognize it would be easy (though expensive) to just start with new rock, I have some very large pieces that I would use in constructing the new reef (if it is safe) that can be re-colonized by the fauna of new rock. I would think some freshwater soaking would take care of any few remaining parasites via osmotic pressure differential, no? Further, I have read that if calcareous cement is used to create a "reef base" by cementing live rock together to create the structural caves and heads of the display to support reef animal/coral placement, such concretions need to be soaked to leach out "undesirables". Soaked in what and for how long?

Second Question:

The new system I am contemplating (dreaming about) could be on the order of 600 gallons in the display. Given that my love is combining the Angels and Tangs in my flock with SPS and some soft corals (which I have done reasonably successfully until this Ick problem, what size sand bed surface area would be necessary, either in a combination of the main tank and sump, or in a separate sump to de-nitrate such a system, given its' fairly high bio-load (well-skimmed), and at what rate would the main system water through-put run into and out of the sump?

I acknowledge I am leaving you with limited details and asking perhaps unusual questions, but my substantial reading on reef topics and care has left me in the dark on these questions. Thank you for your consideration of the above. I also wish to extend my thanks for your many contributions through articles, books and columns, and the practical knowledge they provide to hobbyists like myself. Your efforts are appreciated by many others, I'm sure. I look forward to any advice you can offer.

Regards,

Kurt Oehlberg

Bob replies...

Hi Kurt,

Thanks for a very interesting letter and fully understand the stress to both animals and aquarists that these parasites can cause!

As for copper medications, there are basically two different types on the market - Ionic and Chelated, and its important to understand the difference between them.

Ionic Copper, i.e., copper sulfate, is generally referred to as free ionic copper. It does not stay in solution very long since it quickly precipitates, mainly as copper carbonate. In fact, in an aquarium that contains a calcium carbonate substrate, about 50% of the copper in solution will be absorbed by the carbonate material within the first two hours. Another 20% is absorbed over the next twenty-two hours. Therefore, 75% of the initial copper treatment solution is unavailable at the end of the first day of treatment (Cardeilhac & Whitaker, 1988). Careful and frequent attention must be given to the therapeutic level of ionic copper since it is constantly depositing or bonding itself to substrate, rock, dead coral, etc. Dosage rate for most fishes is .15 to .20 ppm.

Chelated copper medications are also available and stop or slow copper from precipitating out of solution. Their copper is bonded with various compounds, which solves the problem of having to closely monitor copper level. Depending upon what brand is used, dosage level will either slightly or greatly exceed 0.2 ppm.

Even though it might appear that chelated copper is easier to use, I recommend against using a chelated product as an ionic copper is more effective, easily tested, and requires a lower dosage 'level,' even though there's on-going attention and additional dosages. Another possible reason is that some angelfishes, blennies, butterflyfishes, cardinalfishes, dragonets, and wrasses exhibit sensitivity to copper and the lower dosage rate where these fishes are concern might be less stressful for them. Also, keep in mind that gill hyperplasia may occur if copper concentrations exceed recommended levels. So numerous testing is advised when using ionic copper medications. And since it is quite necessary to accurately/precisely know the volume of water in the aquarium to properly treat with a chelated product, many aquarists either under dose or overdose the product.

Velvet disease is caused by the dinoflagellate Amyloodinium ocellatum, and has a life cycle far shorter (about 2 weeks) than Cryptocaryon irritans (28 days), which is caused by a ciliated protozoan. Yet, for both I recommend treatment continue for "at least" 28 days. And keep in mind that raising water temperature is not recommended, and in fact, higher than normal temperatures, i.e., about 85°F is only useful for freshwater Ick. Therefore keep water temperature between 76 - 78°F during treatment.

As for your questions, the reuse of existing rock in the new aquarium should not be a problem. However, I would always keep a "Poly-Filter" in use in the new system, as this is an "excellent" product for removing copper. As for caring for the rock you wish to save, I would take those pieces and allow them to drain well before placing them in a plastic trash can filled with some seawater the same salinity as what the new system will be. I would also attach a canister filter containing pieces of chopped-up Poly-Filters, as cutting them into small quarter-inch pieces significantly increases their area of absorption, and then continue to filter the water in that container(s) until the rock is to be used. That way, they will have reestablished some of their microbial usefulness.

And, I should mention, that any parasites on or in the rock would simply die if they don't have a food source, such as fish to feed upon. Washing or soaking the rock in freshwater is a "hit or miss" situation depending upon what stage the disease causing organisms are in. In my opinion, the method suggested above is the way to go. And, I should also note that probably one or more of the fish to be transported into the new system would be a carrier of either organism, therefore future attention to less stressful tankmates, nutrition, and water quality should be utmost in your planning for the new system. Also, it would be wise to try and keep some cleaner shrimp, preferably Lysmata amboinensis in the aquarium as they can keep minor outbreaks from becoming major problems.

As for cementing rocks together to form caves, etc., its not the way I would proceed. Structurally, there are much better and safer ways, such as drilling small holes through the rock and placing acrylic rods through these holes to connect various rocks together. The drilling process certainly won't harm much of the rock, and the rods will hardy be visible and in fact, if some of the rod is visible, it will probably soon be covered in coralline algae. As for cements, soaking them to remove 'undesirables' as you say, all depends upon what type cements are used. And since I have no idea of what you want to use, can't help you there. However, Portland type cements will radically affect pH, and if this type product is used, it requires many weeks of freshwater soaking with frequent water changes to safely use this type rock.

Question number two, which invites my thoughts as to sandbed depth in the sump and main tank for the purpose of maintaining nitrates at a fairly low level, deserves some background discussion. There's no doubt the plenum method has the best form of nitrate reduction than any other biological filtration method. However, one must understand there are two forms of nitrate reduction - one that reduces nitrate to nitrogen gas and another that reduces it to ammonium, which is a major algae nutrient. So ridding a system of some nitrate with very deep beds directly on the aquarium bottom or with excessive amounts of live rock that mostly reduce it to ammonium is not the way to go in my opinion. But reducing nitrate to nitrogen gas by providing the circumstances generated with the plenum method and/or a very shallow sandbed directly on the aquarium bottom is the way to go, again in my opinion from my well-experienced past practices. And if you don't understand why and how the plenum works, you can visit my website for further information. And as to flow between a remotely connected plenum system and the main tank, flow for the purpose of biological processes is anywhere from the volume of that plenum system to about half its volume per hour. Keep in mind the purpose of that plenum is for the benefits the plenum provides, i.e., better water quality/its microbial processes, not an area for skimmer location or major size water pumps for water movement in the main system. For that, there is a host of other wave making devices on the market.

And if it were to be my new system, the main tank would contain a shallow bed no deeper than two inches of 2 - 5 mm grain sand. And the sump tank (hopefully about half the size of the main tank) would contain the plenum, which should be constructed using the details mentioned on my website or in my booklets.

I hope this is helpful, and keep in mind the toxicity of copper need only be slightly higher than it is in natural seawater, i.e., .001 - .09 ppm, to harm most invertebrates. So again, keep a Poly-Filter in service somewhere in the new system.

Cheers,

Bob

Keywords:

Fish Disease; Copper Treatment

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