I doubt you can yet but do you about when you can tell the genders apart? I found a fish store in my area that carries halfmoons and deltas and double tails. I'm thinking that when I set up a big community tank, after I'm done with college in a year and a half of course, it might be easier to breed the females for the community. This way they would be together from birth and I wouldn't have to worry about introducing a bunch of strange females.