mollies when do you know when to put female mollie in a net tank to have babies.?

Answer 1

1) She is really fat
2) She goes off and hides
3)Starts chasing off other fish

PS- Once you net her. Start feeding her freeze dried brine shrimp. Normally molly need a mix of meaty, and veggie foods, but a high protein diet will speed things up and reduce the chance of death. Plus the better fed the less likely she'll eat her fry. Also the fry need protein, and brine shrimp is a good way to go. (Remember to give both mother and fry need a balanced diet so use flakes every so often.)

Answer 2

she'll look very very round in the belly, almost a square look.
if you move her and she still hasn't had the babies after a good day or so, try raising the tank temperature a couple of degrees.