Need help with separating platies

[23578]

I have 5 adult platies, 3 male and 2 female. I want them to stop breeding because they're only in a 20 gallon tank and it'll soon be overcrowded. I have 13 babies living in a breeder box I have in there. I have another tank that I will move one of the genders to that is a 26 gallon planted tank. Does it matter which gender goes in which tank? The 26 gallon already has 5 guppies and 10 neon tetras and I want them to get along and not be stressed.

Also, several of the babies have a curved spine, and I want to make sure they won't get bullied by the other species of fish, or even the adult platies because I've never introduced them so I don't know how it would go.

I'm not sure what gender any of the babies are yet, so because there would be only 2 or 3 adult platies in each tank if I moved them, would that stress them out too much to not have a lot of platies? I could wait until the babies are old enough to move them so that each tank will have about 8 fish.

Thanks.

[Andy Sager]

Unfortunately, now that the females have been with the males, they no longer need them in order to have more fry so if overcrowding is the potential problem, I would move the males to the smaller tank and keep the females in the larger tank to accommodate the future fry.
As for the fry with bent spines, they really should be euthanized as they are not going to live a healthy life. Malformation of the spine can be from genetics, disease or malnutrition so without knowing which it is, they pose a health threat to the other fish. If these were wild, those fish would be eaten first by other fish. That's Mother Nature at her finest. They really shouldn't be part of the future genepool. (imo)