Once bought a female Umbee that went in a 175G with a Blackbelt male, Sagittae female, Jaguar, 2 Oscars and several smaller Cichlids. Got a bit of grief early on, mainly off the BB, 2 hours later it had claimed half the tank with only the Jaguar half heartedly challenging it from a distance. The Umbee was a couple of inches bigger than the other big hitters at best. Had a small 3" Grammodes once that was plain crazy, a real phyco. Never kept Dovii. Had some nutter Red Devil complex as well, generally find they're ok with smaller fish if plenty of room. Had Black belts and Argentea which are very aggressive also in a push everything else around but not kill them kind of way.