Some Questions

[KrystaK]

My store bought Molly dropped her fry about a week ago and I've picked the ones I'm keeping (I feel bad that I'm basing this completely on their markings at this age - they'll probably change and for all I know I won't like them later)
But anyways, I have some general questions on how I should raise these little guys.

How long can I leave them in the breeder trap? When should I set up the nursery tank for them?
When will I be able to tell what gender they are? - they all look like females right now
When will they be large enough to be at no risk in the tank with other Mollies?

I've read the forums and there is some general information but its not as specific as I like

 

[Seed_Lord]

Aslong as they are big enough not to fit in anyones mouth, they should be fine, as for gender you'll have to keep a close eye out for their...erm...winky, think with live bearers you can get whole batches same sex, prob same with other fish but idk, all my guppys so far have been female from 2 drops

 

[OldMan47]

I would start right in getting that fry tank ready. You could move them today to a tank that was filled with dechlorinated water with a rough temperature match to the birth tank. Molly fry are tough, not sensitive. As long as you monitor the water quality and do water changes as needed, you could even do a fish-in cycle on that fry tank. Fry do not pollute much and they already need frequent large water changes so the difference to doing a fish-in cycle is minimal. I find that I can easily sex a molly that is 3 or 4 months old although they could be placed into a mollies only tank sooner than that.