You don't have to buy a mated pair. If you buy a male and couple females or even just one female you could get them to pair up. If you want to get couple females then you'll need to get rid of the one that doesn't pair up later. If you want to breed them probably best to have the tank the themselfs as like most Cichlids can get very aggressive to tank mates once they pair up and begin to clean off a spot to spawn.