How to pick a male baby betta?

[aemaki09]

Title says it all.

If I go to petco, what are some tricks to determine male from female out of their baby betta selection?

Does anyone have pictures of a clear sex difference at that young of age?

I know the basics, ventral length, beard, and egg spot......but their babies are normally too small to see egg spots on, too young to flare, and every time I grab the baby with the longest ventrals that is in a tail type I want, it still ends up being female.

I just really want to see their fins grow for future referance on HM spawns. And because I think juvies with half-length fins are sooo cute! (I have a blue grizzle HM juvie that is just to die for with his stubby fins!)

Can someone help me?

[BettaGIRL5]

I have noticed that on almost all male bettas their flaring fins( the thing i call when they puff Their gills up) hangs out from underneath and you can see it even if they aren't flaring. None of my females have it so it might be a male betta thing :) just something to keep in mind

[Hadoken Kitty]

I know you mentioned that they're too young but....have you tried taking a mirror?