I should know these by now. *sigh* What is worse, an air cell that is too small or too big in the final three days? What would cause variations in air cell sizes in eggs that are the exact same age, in the exact same incubator with the same temp and humidity? I have 10 ducklings due tomorrow, two have larger air cells and as of last night, had internally pipped. The other 8 have quite a bit smaller air cells, only at the top of the egg and had not pipped as of last night. My incubator always says only a bit over 40% humidity, no matter how much water or how many containers of water that I put in there. It's an older sportsman. I had plenty of chicks hatch out just fine with no humidity issues so I don't know if that's the issue or what. I cannot pull the humidity up no matter what I do. I've tried. So, air cells...talk to me please?