once your babies hatch you might want to put a sponge (aquaclear filter sponge with a hole cut in the vcentre) over the intake of your filter so babies dont go init lol. i learned the hard way!
also- pristine water conditions are necessary, as baby fish release griowth hormones that inhibit the size of their siblings. 10% daily!
Check to see if the have a dark dot inside if they do then they are fertilized if they don't have a dark dot then they are not fertilized. If your not sure then just leave it and wait and see if they hatch.
my cory cats where chasing each other nearly all and then decided to lay eggs which look tiny white. how do i know they are fertilize? i have good water flow in my tank, i separate some of the eggs carefully into breeding net