How big are they?
Also how much Lol.
I have only seen a few of these guys around, if you really mean the true one, which name escapes me at present. You should buy them all and breed them mate.
They are peaceful for a cichlid and like being in groups.
We had 12 x 6inch in our tank for a while but didnt have the time to get them to breed for me. They may be a little shy until they get used to there surroundings.
I havent kept them with many other fish, oscars, jags and a few others. In the 6months I had them all they did is swim,eat and poop Lol. They never messed with the others and they where left alone also.
Good luck,
Joel