My eggs have been in the incubator for 7 days now. I started with 16eggs. I candled them last night and 11 eggs were good and 5 were duds. Each egg that is fertile has a black spot about the size of nickel and all are moving around. One egg had a big air sac. The air sac was partially at the large end of the egg and went towards the small end. I would say it covered 35-40% of the egg. The egg is fertile and the little chick inside is moving around a lot. My question is will it survive because the air sac is so big? This is my first time hatching eggs and I'm using my homemade incubator. Very exciting!!