Quick history: I had a very small tank (24L) in which I kept 3 sunset platy (2F, 1M). Needless to say, they mated and I didn't get the pregnant females out in time before they gave birth. So I now have 15 platy! The male died soon after, no sign of disease or distress, I believe he was just old as he was already adult size when I got him from my LFS. Everyone has since been moved to a 125L tank and they're doing well - obviously much happier in their larger home. Question: all the platy fry are growing well, but they all appear to be female. They're about 3 months old at the moment, is it safe to assume I have an all female tank now? I would rather not have them mating again, and with no signs of aggression between them, I'm happy to leave it as is. But I want to be vigilant if there's a chance there might be male among them and I just can't see the gonopodium until they get a bit bigger.