I think I have just learned the answer to this question. I just bought several apisto and west African species at the Atlanta Aquarium Club fall auction a couple of weekends ago (had a great time!!!). This morning a female A. pertensis greeted me at the front glass of the tanks next door to the tank she was in yesterday!!! I'm grateful that she is not on the floor! The reason I didn't want covers is because my lighting is from 4' flouresent "shop lights" hanging above the tanks. I'm afraid a glass or plexiglass cover would limit the light for the plants I am trying to grow. So my question is... do you all have covers on your apisto tanks???