shells to hard for chicks to hatch

[veggiecanner]

The last 14-15 eggs in my incubator didn't hatch and I opened them, they were so hard I had to whack them with the side of my knife blade.
Any idea why these would be so hard when the ones that did hatch had gotten thin enough for the chicks to zip them.
This seems like it happened my fist incubator load too. After being in the incubator for 18 days seems like they should have gotten softer.

 

[chrishw]

Are you keeping the humidity about right? Like using hydrating pads or automatic system of hydration?

 

[veggiecanner]

65% yes, thing that got me is some were able to hatch Others were very hardThe hard ones were not able to pip.

 

[chick moma]

I am having this same problem. The babies just can't get out of their egg!!
I have adjusted to humidity to bring it up to about 75% so hopefully that will help. I will keep watching to see what responses you get! Thanks

 

[buttonquailtx]

Do you give the parents any calcium supplement like oyster shell?

 

[chick moma]

I have purposely not given my quail parents any calcium because the shells are so hard!! Even cracking the eggs to eat is hard! The chickens yes their shells are thin, but they are on opposite sides of the pasture and share nothing!

 

[veggiecanner]

I thought it was because I was feeding Purina Layena and oyster shell. so I quit the oyster shell. But i was holding a newly layed egg and put my thumb through it. So I put them back on oyster shell.

On lock down now and having trouble keeping over 60% humidity. Just added wet spounges to the Incubator.