I hatch a lot of coturnix quail eggs, and they will hatch about 3 days apart sometimes. They will set in the eggs pip for days, and the sac will dry up and stick to them. I try to keep the humidity at around 60%.
Husband has been hatching his at bobwhite at 75% humidity...no sticking, all done within 24 hours, no problems.
I wish I could help--that is very strange. We have had tremendous luck hatching coturnix, even under less than ideal circumstances. They just don't ever seem to have any problems for us. Out of 40 fertile eggs recently, only two did not hatch--one had a crossed beak and the other was positioned upside down. ALL the rest hatched. And those were incubated at too high a humidity in an incubator with another 20 *infertile* eggs that went rotten and one exploded (not the usual circumstances--I won't try to explain--just one of those things). So..... I'm afraid I'm not much help, lol! What is your ambient humidity? Are you located in a very dry place? I know with duck eggs (something I have more experience with, and less ready luck with), the humidity in the room affects the development of the air cell as well as the hatchability of developed babies as much as the humidity inside the incubator. We live in a humid climate, so I struggle with keeping humidity LOW enough, rarely do I have trouble with it getting too high. I know that if you ambient humidity is very low, you need a higher internal humidity to compensate. Good luck--sorry I'm not much help. I hope it gets better.
