eggs in water

I picked up a pair of snappers from someone a few weeks ago. They told me they though it was a pair and they were living together in a small bucket. they were very skinny, so i separated them and have been feeding them fish and chicken livers, i cleaned one of there stock tanks, and found pieces of egg shell, no fetus, should i assume they are infertile, and just let her keep laying in the water of is there some way that i can get her to drop the rest of the eggs onto some land and maybe incubate, never dealt with breeding turtles, i just wanted to get them out of a bad situation. please help fast.