I've had this debate with lots of people and what it really comes down to is: it depends.
Do you have a sump? Skimmer? Lots of live rock? Do you have a heavy bioload from corals? Are the fish you are planning on free swimming or bottom dwelling? How big do they get?
Right now I am running my 40g without a sump (being rebuilt) with several colonies and I had 8 fish (most I gave away when I moved recently) BUT they were all mostly smaller species AND they were a mix of free swimming and bottom dwelling AND they are not agressive. So... it depends.
As a rule of thumb I wouldn't go more than 0.5" of fish per gallon.
|