Well, what's going in the tank with them? You could do a Clown Pleco, Bristlenose Pleco, Rubberlip or one of the smaller species. You could do a Butterfly Loach. I used to have some Dwarf Bristlenose Plecos, they were awesome. I haven't seen them around in quite a while though. You could go with snails or something too. It depends on what you're going for.