The female will lay eggs anywhere between 2wks to 7wks. If female is mean to the male,(meaning the male isn't her mate, but a threat to her and eggs) it explains the eggs being gone. She felt the danger and ate all the eggs.
Hopefully they will do better next time. However, if the female is mean to the male constantly, they will never be mates and suggest you go find another mate for each one of them.