Some of my favorites that I've been looking at- loiselle's, synspilum, jags, trimac, carpintis. Those are all large so you wouldn't prob put much else other than one or two of those with maybe a few smaller cichlids that were tough enough. I think the loiselle's and jags may not put up with tank mates at all in a 125 but I don't know for sure. If you want more then one or two big guys look at a more peaceful set up with a Green terror, severums, oscars, and similar disposition fish. Depending one which ones you go with you could probably have a few together.