Thanks for the responses. I had moved the incubator downstairs to an unused bedroom where the temperatures would be more stable. I did not rotate the position of the eggs in the incubator or use the cool down cycle. I will definitely try those strategies next time. I can also try the heat syncs. I have an automatic turner, so I do not turn by hand. I believe that it rotates the eggs 3 times a day, but I would have to go find the directions to be sure. I have recently been giving them kale from my garden, but wasn't during the time frame that I collected the eggs. I am thinking that grower feed is the same as Broiler feed. Is that correct or not?
Grower feed is very similar to broiler feed. Calf Manna is a great supplement and is not too expensive. The bag has feeding instructions for chickens on it too.
I bet you will have a better hatch next time!
What is your incubator?