Tough to say, but dovii don't get truly dominate till they get over 13''s or so. So assuming a dovii was Full grown @ 6" with the same temperament and weapons as a full grown dovii, then you would have to say a dovii. Just based on the fact that no other cichlid has the weaponry of a dovii, not to mention that you will NEVER see a fish hit the tank or tank mates harder than a dovii will. Anybody who has seen a dovii go agro will agree to that I am sure.