Add water flow...
I have a good enough filter in my tank but the output is only on one side. Bio-film is forming on the water surface and it bothers me. I'm thinking of adding another filter. Maybe a fluval 205 just to add water flow on one side. The additional filtration is unnecessary. I just want to disturb the water surface on both sides of the tank. Is there any device, some sort of pump that will increase flow? Even without filtering at the same time? No air pumps. Thanks.