I would have to say geophagus orange head tapajos 1. Also called redhead Tapajos. Do not confuse this fish with peach faced tapajos 2 which gets no orange-red color on the head when it matures. Geophagus Altrifons takes secound place for me but be fowarned 12 inch specimens are not uncommon. The orange heads will max out at 7 inches for males.