No, I didn't weigh eggs. The humidity stayed at 25-30% without adding any water, so I left it at that. Perhaps I should have increased it at the end? Why would 5 hatch fine at those levels and not the other 5? Seems as though if I adjusted humidity to get a perfect weight loss on the 5 that didn't hatch (assuming that was the trouble) wouldn't that have impacted the 5 that hatched fine with no help? Also, as a side note we had a power outage between the time those 5 hatched and others did not. The power was out 2 hours and we put blankets over incubator but it still was a critical time to have that happen. Thanks for the opinions and help.
my best guess is you didn't have proper air flow...these eggs put off a LOT of CO2 during incubation and they need excellent air flow/exchange the entire time, especially near the end .
Leaving the vents open in the back as much as you can the entire incubation period while still maintaining your proper humidity & temp. assures they get much needed oxygen and the bad air is also vented OUT of the machine.
The blankets prob. blocked air flow, the 2 hours w/out power at that stage prob. did little harm in itself. I've had a power outage for 5 hours mid stage and still had a good hatch .
The pores in the eggs take in air, block it off and they suffocate in the eggs.
I honestly don't think you had " shrink wrap" at that stage, it's called drawdown...I do believe it's a very good chance suffocation was your problem.
As far as your humidity goes unless you weigh the eggs and kept up with the weight losses the entire time then you have no idea what the ideal humidity was for each individual egg.
Per tagging them, ever thought about microchips? With only 5 chicks on the ground it may not even be necessary, you will be able to tell them apart as they grow..most are very unique in their own ways . You will see this as time goes by.