All eggs didn’t hatch

[Danielle_14]

Hi, I put 12 eggs in incubator, day 10 I took 5 eggs out due to no development, day 18 put remaining 7 into lockdown with humidity at 55-65% temp at 37.7-37.8 all developed Nicely & moving about when candled, day 21 came and went with no pipping or chicks hatched, waited a couple more days still nothing, what could have gone wrong for none to hatch?

 

[Mellowmalt]

hard to say what could have gone wrong but I will mention that I use slightly different conditions.
Towards the end of incubation I lower temps slightly so although 37.5-37.8 is perfect for the first week, in the last week 37.8 can be quite high and I run my incubator 0.5 degrees lower than this.
Your humidity was a bit low too for the last 3 days, I aim for 65% minimum during lockdown.

 

[Danielle_14]

hard to say what could have gone wrong but I will mention that I use slightly different conditions.
Towards the end of incubation I lower temps slightly so although 37.5-37.8 is perfect for the first week, in the last week 37.8 can be quite high and I run my incubator 0.5 degrees lower than this.
Your humidity was a bit low too for the last 3 days, I aim for 65% minimum during lockdown.

Thanks I was doing what I was told to do for my local feed shop person that does heaps of incubating. Will try again and see what happens, so maybe set temp 37.3 after day 18, and humidity 65% up but how much humidity is to much?