Can cleaner fish live in a clean tank?
The only "Cleaner fish" that I know of is the Marine species called the "Cleaner Wrasse". These fish pick parasites off other fish and will even swim into larger fishes gills and mouths to clean them too. If you are thinking of Catfish as being cleaner fish, then you have got things very wrong. Catfish are bottom dwelling fish but they do not clean up dirt and rubbish. They need fresh food just like any other fish. To the best of my knowledge no species of fish do well in a dirty tank.