Should have 20 or so but each case is not the same. I've heard reports of only 8... It would never hurt to put a prekilled prey because they pose no threat but I guess it would depend on the last time she ate... and if she is stressed or not . Congrats by the way!
ps: Do you have any pics pre-pop?? I have a c grac. that keeps getting bigger not sure if she is pregnant or just getting fat haha