One of my favorites, I've kept them with everything from angels, oscars to various Central Americans, I remember I used to have a male that would spar with a black belt not your typical geo...
I am pretty geo illiterate, but have been thinking of acquiring a single red hump. Are they best kept in groups or are they fine as singles with other slightly larger fish? (eg, with a single chocolate cichlid or a single severum in a 120 gal.