Well the males develop there gonopodium at about 4 months old so that's when you should be able to tell the gonopodium id like their anal fin!! pretty much all male livebearers will have a long pointy one and females have a normal anal fin!!
I have babies between 2 weeks and 3 months and none have there gonopodiums yet so i'll have to wait too!!! it's a cool suprise.
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Adam
"I'd rather be a could-be if I cannot be an are; because a could-be is a maybe who is reaching for a star. I'd rather be a has-been than a might-have-been, by far; for a might have-been has never been, but a has was once an are."
-Milton Berle |