It may seem stupid but what are you hoping to "clean?" Are you talking about cleaners of fish (eg neon gobies) or things that may clean the tank (eg catfish in freshwater)? Sorry if it is a stupid question but want to clarify that.
OK then I agree with Bang Guy - though my sixline could care less about any other fish except that one on the other side of the glass that looks like him I prefer neon gobies, or potentially cleaner shrimp (not all will clean though ) but definitely NOT cleaner wrasse.
I agree with Bang Guy - though my sixline could care less about any other fish except that one on the other side of the glass that looks like him 