References - Cycling (Curing) Live Rock
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Cycling (Curing) Live Rock

Albert J. Thiel


A lot has been written about reef aquariums and their cycling process, starting with "cured" live rock, how much live rock to purchase because it is needed in the tank, and what kind you should get. These methods certainly work and lead to tanks that will, in the long run, do just fine and will allow you to maintain corals and fishes using any one of the filtration methods now in vogue (trickle filter, Berlin, Live sand, plus combinations of any of these which, I find through personal communications with them, many, many hobbyists nowadays do). My personal experience confirms this and, therefore, I certainly do not want to discourage you at all from adhering to any of those suggestions since they are all viable solutions to running successful reef aquariums.

I would like to propose though that you can cycle the aquarium with "uncured" rock and end up with more life-forms on the rock than when you use cured, yet have as good a water quality at the end of the biological cycle, if not better. Note that I wrote the better aquarium as that is indeed what I have found. That is the method I now follow myself as well as recommend and that I would like to suggest to you too because I have had such good success with it. The only caveat is that you will need a little more patience. Indeed, you will have to go through a full 28-30 day biological cycle without any additional animals added to the tank.

Uncured live rock tends to be less expensive and, in addition to giving you very potent biological filtration and denitrification (nitrate reduction), this method thus saves money at the same time! With all the other expenses you face this is a benefit that is not to be overlooked. Curing the "live rock" yourself also has the advantage that you are in full control of the process. Don't overlook this benefit! You decide what to scrape or clean off the rock at all stages of the cycle beginning with "before" the live rock is placed in the tank and continuing through the entire cycle when the rock "is" in the aquarium. Would you not prefer to be in charge rather than have to rely on what you were sent by the supplier and the manner in which he or she cured the rock you received, often with very few life-forms left on it? The manner in which they cycle does just that. The rock you get will be pretty bare. I certainly would, especially after having seen how the cured rock comes in and how it is shipped. Very few life-forms are left and the only thing the supplier concentrated on was getting rock to you that had a bacterial bed. But, then, how much of that bacterial growth bed is really left after an overnight shipping trip? Not much, in my experience, as the half- life of the bacteria is around 4 to 5 hours. The trip takes 24, or more, which is likely to kill off most of the bacterial bed anyway. What you end up with is "clean" rock with very few, if any, bacteria on it! You will have to cycle that rock all over in your tank. Because of the little amount of life-forms left this may take quite some time, unless you add organic material to the tank to create ammonia and start the biological growth cycle up. Having said all that, I prefer to start with totally uncured live rock and go through all the steps myself, keeping control over what happens all the time.

Here is an outline of the method I use:

This method has worked for me and many others to whom I have recommended it. It will work for you too. A last note: as you increase the biological load in the tank you should add more rock as well. The procedures that apply to this additional rock are the same as the ones explained. Because you already have a biological filter established when you add this supplemental rock, the cycling will go much faster. You may,in fact, not even notice it. Add about 0.5 pounds per gallon, at a time. Stop when you are satisfied that you have enough rock in the aquarium.

This material was obtained from Compuserve's Fishnet Computer Service

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