Incubating is enough to drive a person crazy! I had about a 98% hatch rate for a while. I don't remember what happened but suddenly my chicks were all hatching on day 19 and had huge navels. So I lowered the temperature. 3 thermometers can also drive a person crazy. Now I've been having fully developed chicks die in the egg and they're hatching on day 24 and 25. Temp is going back up. I've had about enough of this LG. Too bad my Brinsea only holds 24. Next year I'll invest in another Brinsea, if I had room for the cabinet incubator I would already have it.