how soon can Livebearers start breeding?

[Bottomfeeder]

^^^Title
i separated my mosquitofish fry because at 3 mos old i cant sex them and i dont want them to start breeding. (I have heard that they can start at a month or so old) but im having trouble controlling waste in the small containers. so when could the start breeding? it would be easier to put them all together in a big container but I cant accommodate a ton of fry

 

[micstarz]

Approximately 6 months.
Just let them eat their fry...or alternatively, if you have bigger fish...feed them like flakes.