If you're talking about breeding different tail types, yes you can, but the result may not be what you want.
I posted this in a diffrent form, I didn't relies THIS form was here DXLittleBeta said:I'm thinking of possibly breeding my Betta but I would like to know what the minimum size would be. All so could you use a split tank for breeding? As in having a fish living on one side but use the other side for breeding?