well in my opinion i would go to your retailer and buy some sort of breeding trap (the ones that only the mum goes in and the babys drop into your main tank) and then in that case the mum is no danger to the fry , what is in the tank you were talking about just the mum and the babys??????? .
or you could get some floating plants and put that in your atnk then that way the mum cant get the fry as they are in amongst the plants on the surface,
which ever you choose congratulations
ashley

( keep us posted on wats happening)