Because they like the fish?
Not all green terrors and jack dempseys can be kept in a community. You can have a lot of violence in a community tank of aggressive cichlids. Single cichlids in a tank can be referred to as a "wet pet."
Personally, I prefer communities or pairs at least, I like watching the interaction, but I can see why some might want to keep a single fish. Also, say you had a pair and the male killed one or multiple partners? That happens a lot and the owner liked the fish so it gets housed alone.
Not all green terrors and jack dempseys can be kept in a community. You can have a lot of violence in a community tank of aggressive cichlids. Single cichlids in a tank can be referred to as a "wet pet."
Personally, I prefer communities or pairs at least, I like watching the interaction, but I can see why some might want to keep a single fish. Also, say you had a pair and the male killed one or multiple partners? That happens a lot and the owner liked the fish so it gets housed alone.



Why do people like a solo fish ? are midas' more fun when they are paired ??