Do you have a picture? That is very strange. Do you see any blood around the spot? Does it look like the crack came from the inside-out? Could you have accidentally hit something on it?
Oh man. I am so sorry! That stinks!
well not much you can do seem to have big problem with mal positioned chicks when using the plastic egg turner past 15 days, but get temp spikes when they pip if I put them down on the plastic on the bottom of the incubator when they try to hatch
Eggtopsy results are 11 died day 18-19 and 25 were malpositioned died in shell, head between the legs for most part
1 live chick doing great called her speedy lol
sanitizing to prepare for another try