I've had good hatches and bad hatches, u gotta figure out why in order to fix prob. That means u gotta look at insides of the eggs. First, temp has to be accurate and consistent, cannot vary. Get 2good thermometers and calibrate. I know my body temp is about 98.3, thats what I use to ck. I dry hatch 1st18 days, drowned too many in process. U know cuz when u crack them open u have partially or fully developed chicks swimming in water. Hope this helps..