Fish breeding for Livebearers. I’ve got 12 fish, 3 platties, guppies and molly females & 1 male of each. Am I almost guaranteed baby fish?

Therno absolute guarantee or formula tomake them breed but if the temps right and they are not stressed they should breed.

They are going to breed for sure, being livebearers. What the 3 females per male ratio does is ensure that you will have the max amount of fry (since the females will each give birth to big batches) and that the male's harassment of the females is spread out so the females get a little rest and are not harassed to mate repeatedly to the point it is dangerous to their health. So you are doing great, and will soon have lots of and lots of babies appearing.

If you are breeding them for specific traits, something to keep in mind. For this first batch, it is possible some of the females are already pregnant and into the gestation period by the time they met your male, so don't be surprised if they give birth a little early to fry that may not necessarily be your male's offspring. But although they do store sperm, they like to use the newest packets of it, so the second batches of fry each female has will be fathered by the male you chose for them.

You'd be guaranteed babies with one female if she'd ever been in a tank with a male.

Sooooo, yes, babies are guaranteed.

Note: "ratio of male to females (3 to 1)"

No, female to male 3 to 1

Get as many large plastic plants as you can and more babies will survive.

Get one of these too.

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