Read this thread

http://www.maast.org/index.php?name=...ic&t=16192

The biggest question is what fish? A 10 inch grouper or a 2 inch goby? What kind of filtration are you using? What else do you want to put in the tank with the fish? Cut and dried answers rarely work in this hobby. There are just to many variables. My answer is to slowly add fish and monitor water quality until you reach a point that your system will no longer support additional stocking. You might want to pick up Mike Paletta's book. It has a lot of information about stocking a fish only system. Yes, that means a doing more research. Get used to it, it comes with this hobby. We never stop learning.