I have a wet/dry (or trickling) filter on my reef tank. I have had the tank running for a while, and have had no problems. However, recently I have read once on this forum and once at the Simplified Reef Keeping (Robert Metelsky) web site that I should not use the bio-ball media in the filter. Mr. Metelsky states that the media promotes growth of the wrong types of algae, and actually leads to greater nitrate concentrations. However, he does not explain in enough detail that I can understand why.
I would think that there would be little
algae growth in my filter, as I have it underneath the aquarium and it gets little light. However, the bacteria grow a very nice biofilm, of which the lowest layer is likely to be anoxic and remove some excess nitrate. The remaining nitrate should be taken up by the corraline and other algaes that receive light in my tank.
I need help understanding the logic of removing the bio-balls. Also, I read that a lot of people have refugiums, but I don't really have a good idea of what they are, how they are set-up, and how they work. They appear to be deep sand filters, but I am not sure.
Thanks for the help, and I hope to meet some of you at the next ARC meeting.
-Chris
