Nice! That is good you are getting them at that size because they are very slow growers. I bought this one at 2" 3 years ago and is now around 5". I don't know about the sex of mine either. Are you looking to get a pair? Can you post pics?
Thanks, I am worried the loisellie will be too aggressive for these guys. That is why I got a small one hoping that the others will establish dominance from the start. Not sure if that will work. So far the tank is fairly peaceful and the fish range from 5-10". My astyanax tend to harrass and eat small cichlids. I've lost just about any HRP fry or 2" fish to them.