Sorry for posting another quesiton about molly fry, but I need to make a few clarifications and add another question

I don’t have a second aquarium at this time. I’m saving to buy a 75 gallon… but right now the only other tank I have is a 15 gallon that holds my Betta, whose not very mellow so he’d kill the momma before she’d give birth.

I was thinking of using something like this: http://www.aquarist-classifieds.co.uk/forum/upload/breeder-trap.jpg

but someone told me that’s not a good idea.

I have four plants in the tank right now… three are silk and one is real tall grass…

should I get the net or add more plants and just let them go as is? and if I let them go as is, how do I feed them. Someone told me to feed molly fry newly hatched brine shrimp… can they also eat small crumbled particles of the flake food?

I just want to make sure some of the babies survive. I’ve never had baby fish before, and I’d love to watch them grow up so I want to do whatever I can to protect them.