Breeding question: How do I know when my mollie will give birth?

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Hopeless Romantic
Nov 7, 2002
When my swordtail was pregnant, you could kinda see the babies through her body (she was clearish gold). But now I have a mollie that I think is pregnant, so how can I tell? and how will I know when she will have the babies? (so I can get her in her own tank before.


Sharyl C

Mola and Me
Mollies are somewhat similar to swordtails. You should be able to see a dark area toward the back of the belly if the female is pregnant (with black mollies this can be difficult). I'm not sure what the exact gestation period is for mollies but you should be able to find it somewhere on the internet because they are a quite popular species.

I have a group of sailfin mollies in a tank. Along with the adults there are about 60 fry from 3 different broods, diamond killis, and 2 small white mullet. Everyone seems content and I have not seen any of the adult fish chasing or picking on the fry.

Good Luck with your babies