Good advice
I take it you have nothing else in your tank?
I have Platies and found a few babies in my tank when cleaning it one day!
The thing with babies you need to be careful as if someone in the tank has a mouth bigger than they are- they will get eaten- parents or not!

Also the filter in your tank might be too powerful for them and they can get stuck to it or sucked into it and die.
When I can see that one of my platy is really fat- they look almost box shaped before birth- I move her into a plastic breeding trap in my fry tank. The problem with leaving them in the net is they will still get eatin if you aren't quick enough.
I was lucky enough to see my female give birth and discoveered that the fry don't move when born, they just sink to the bottom. So if they had been in a net, when the mum turned round, she could eat them! With the plastic trap they fall through the slits to safety.
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