Are they carpintis? I'm sure the venting is more accurate but usually females have a black blotch on there dorsal fins. Sorry I couldn't help on the vents gl though
Yeah that's a tough one bc your right not all females have the black blotch on dorsal. You have some very pretty ones so maybe the higher quality females don't have the black spot who knows. But they are stunners, have you seen any pair off or do mating behavior in the tanks ?All of the 12 that I originally got from the collector, didn't have a spot on the dorsal fin. So idk what to do at this point.
My guess first two male,last female,I wouldn't handle them anymore as that stresses fish.