Originally Posted by DJOstrichHead
alright well i dont want to overtax my bioload in the 30 gal and i only planed on keeping 3 fish. would my 36# of live rock allow me to push that to 4 or is that too far. I would like to split up the areas that my fish live in to prevent competition for the same food and since i already have a benthic fish i was wanting a free floater like a bangaii cardinalfish or something along that line maybe a firefish. What is a third niche of the tank for another fish to fill?
The number of fish going into a tank is dependent on more than just waste load. Territory says everything, but so does oxygen content in the water. A 30 gallon tank is not going to safely hold more than 3 small fish when you combine the things that determine the number of them.
Cardinals, especially the bangai, don't do well as a single fish of their own species in a tank. They are a schooling fish and the stress of being alone can cause enough stress to be fatal. A firefish, even though also a schooling fish, has a much better chance of surviving as a single of their species. Another idea would be a neon goby... 1 of those by itself could thrive, and stay small and still offer you a lot of color. Neon gobys are mid level fish, and very peaceful.