I love my zebra nerites. They keep my 2 5 gallon tanks spotless. My anubias in both tanks continually get covered in brown diatoms, and then the nerites find it and clean it off completely. I have a weekly cycle in my tank of the anubias gradually getting browner and browner and then the nerites cleaning it again. Without them my tanks would be covered in algae. They really are the best algae eaters and I can't think of any that could do better in a small tank.