That's a good idea too, put the two smaller on one side and the larger ones on the other. Since the big drawback to pulling them is they will be the new fish in a established territory(s) when I eventually put them back. And we all know how rough that can be. I wish there was an easier way to sex them at this size. However I doubt I can learn much at 2-3inches unless there is a give-away I've missed in my research.