This seems to be the case with amatitlania-types. My jumbo male panamensis that killed his female in a 90 gallon, is now living happily amongst community fish in a 45 gallon planted tank. They just go nuts when that breeding aggression kicks in, and if they don't have anybody else to chase, they let it all out on the female. Fish that they don't see as a threat (non cichlids) are usually ignored.I will say this. I've got the single male in his 40b now with swords, sae's, two baby hoplo cats, an l183 pleco and kuhli loaches and he's a perfect community fish. He's just rough on females. I think you'll be fine in a 75 especially with other targets. I just don't think this species does well when it's just a pair without any other cichlids to target.
