Well I decided to give it one more attempt before giving up on this little incubator. I set a dozen eggs, 10 from my mature polish flock (year old hens & an EE Roo) and two from my younger layer in my other flock.
Of the 12 I set 11 made it to lock down. There was one egg that had a crack so I sealed it with wax around day 14. Ultimately it was a late quitter, I suspect bacterial contamination.
Of the 11 that went into lock down I ended up with 9 chicks. 2 eggs were late quitters, the one with the crack & one from my younger chantecler cross hen. Both looked like they died around day 18/19 on eggtopsy.
The chicks from the mature hens hatched in quick succession all 8 hatching within about 16 hours of each other moving very quickly from pip to zip to out. The one pullet egg that pipped did not advance beyond a pip for nearly 18 hours and I ended up assisting. Chick was malpositioned and could not turn to zip. I was dubious about it last night but left it in the bator to fluff up and this morning it is bright & active.
The only changes I made to this run was to move the incubator to a smaller room to help avoid temperature swings & to use eggs from mature hens. The difference was dramatic taking my hatch from 20% to over 80%.
That's a great hatch rate! I always do awfully hatching chickens which is why I only hatch ducks now.
