Thanks, that helps out a lot. The reason I'm asking this is beacuse I have 75 gallon that has a few small fish like danios, australian blue-eyes, tetras, three gold barbs, peacock gobies, small silver dollars, a goodied, and a platy which I intend on moving to a different set-up. By doning this I will allow the tank to be occupied by other larger fish. I do have an adult Keyhole cichlid, 2 Angelfish, an adult Silver Dollar, an Elephant-nose fish, and a dwarf gouurami that I will keep in the 75 gallon. I will probably keep the young Silver Dollars in the other set-up until they can grow a bit larger and then re-introduce them back in to the 75 gallon.