are you hatching in same incubator, that was my biggest problem , The incubator would freak out and fry them during lock down, got another one that wasn't so negative when i upped the humidity for hatching at lock down and set it up 24 hours before needing itand went from 0-2 no matter how many eggs I put in and trying to stay awake 3 days to watch for the spikes to an 83% hatch rate, don't give up hope, these wonderful people talked me through a few failed hatches and helped figure otu what it was that was going on with themThanks to all who helped. I think I found the problem. I set up incubator two full days before I set any eggs and calibrated everything. Checked for accuracy. I just put a thermostat in and two more hydrometers that I knew were accurate before because I tested them. Now the temp says constant but thermometer inside is reading 105 deg and the other two hydro says 85%. I’m pretty upset at this since I spent so much time testing. I had calibrated 7 hydrometers and 5 thermostats. And only out 2% and bang on with temp. However if temp was high then why were eggs all alive and proper weights for lock down? I’m frustrated even more now. Maybe tomorrow I’ll crack them open and see