About 5-8, 1.5-2 inch fish such as platies, guppies, small, non-nippy tetras and rasboras, cory catfish, small gouramies and some of the smallest, peaceful loaches. Obviously, you need to also consider their behaviour and whether or not they are territorial, aggressive or schooling, social species, whether or not they are compatible with your other selection of fish and of course you need to make sure you are calculating based on adult sizes.