i tried to hatch out 35 chicken eggs and all but five didnt make it.. on day 12 everything looked great. but on hatching day not so good 5 didnt make it all the way out of the shell. i peeled the shells out of the last 3 that did make it. the membrane under the shell was very thick and hard to tear.. the rest out the eggs looked like they died a few days before hatching day. i am using the little giant incubators. i have heard this are hard to master..