Until recently I had a couple of tanks, but I ended up combining them all in a 65 gallon tank. They are all fresh water tropical fish except for some comets that are in there for the summer. I know it sounds crazy, but I've also got 3 convict chiclids in there--even though it's a mixed tank. They are very peaceful and mostly ignore the other fish. They sometimes chase each other around a bit though. Don't ask me how it works, but it does.