At about what size do these guys start coloring up if they're male? I just picked up a 3"er in hopes for a male. It was the dominant one with the others, and the largest. Thanks everyone.
Actually, you might get a better response in the Rift Lakes Forum= Oxyrhynchus is Malawian in origin. They get quite large but if you got the one in charge, it will almost certainly be a male & should start showing some blue coloration anytime now unless it is being suppressed be other tank inhabitants.