What ehatcher said! We took his advice and had like a 99% hatch rate out of our fertile eggs. Only one didn't hatch because it was starting to pip, but we were going out of town so we put it, with the deli cup open into the hatchling rack. When we came home, it hadn't hatched.
We used a hovabator, deli cups with damp vermiculite, and had a sealed plastic bag of water in the bottom of the incubator. All our babies hatched out and are healthy little ones!