The problem here is that I can't see the clowns and estimate their age. At a certain point clowns, even in a large group, can stop being juveniles and start asserting themselves. I constantly have groups of clowns at the store and they can come in larger than we usually get... about an inch to an inch and a half or so. At this point we start seeing aggression as the dominant ones start vying for the "top spot". I'm often in the position of helping customers pick the clowns they like best and at the same time attempt to steer them away from two clowns that look like they are already transitioning into a female. It takes a while for the "change" to happen but once it starts happening they can't stop and turn back. So if yours had already started that transition then at some point a war would start in your tank. Again, I'm just speculating because over the internet it's pretty difficult to decisively say "you have two females" or "they are just figuring it out".