Hatching in an incubator — advice

[RachsChix]

This is my second time ever trying to hatch my own eggs. I had only 1 hatch my first go around so I got a new incubator because the one I was initially using was an old hand me down.
Round 2, I followed everything. Candled at day 18 and got them ready to go for lockdown.
4 hatched… on day 19… one of which died. And no others hatched. I opened them up and each one had what looks like a full (but deceased) baby inside.
What is happening. My temp said it was good. Humidity was between 64-70. I have a little extra gadget in there that read humidity and temp. The temp on that one was reading between 98-101 and temp gauge on the incubator stayed around 100.5. Why did all my babies die
12 looked like the 1st photo. And the other 3 looked similar to the 2nd photo. What am I doing wrong. … can someone please tell me when (about) they died so I can try to figure out what I’m doing. I’m so heartbroken over this.

 

[chelseachook]

101 is a tad bit high - which may have caused the early hatch. I may be wrong but the chicks look like they died around 15 days? So sorry you had a bad hatch

 

[kmpcfp]

My guess would be that humidity is too high throughout incubation. How big were their air cells? Were they positioned correctly for hatch?

 

[kmpcfp]

Also, how are you counting your days? The first looks nearly full term, just didn't absorb the yolk all the way. The 2nd looks like it died a little sooner. Are you using a forced air or still air incubator? If the temp is consistently swinging between 98 and 101 very often, then it would average to be 99.5, which in a forced air incubator would be okay. If it is actually 100.5 like your other thermometer, then it would be a little high, but I wouldn't expect them all to develop so far. Did you have any early deaths?