Most small tetras, cory cats, pigmy gouramis, dwarf crayfish, shrimp. I would go with lemon tetras, or neons. Corys no matter what, 4-6 of them. The pigmy gouramis are very cool lookng and 1/3 the size of a dwarf gouramis. You could go with a lot of different killie fish, they are beautiful and the eggs will make a nice snack for somebody.