What Did I Do Wrong?

[ChickenCanoe]

Another thing to consider when comparing thermometers is, as you have noted, is response time. Some take 10 minutes or more to get an accurate reading, some are almost instantaneous, like the one I recommended.
Since the incubator heat source cycles on and off, that can really mess with someone's head.
ETA
The instant read will fluctuate with the heat element, the slow one will be way behind. And the instant read will be much higher than the eggs when the heat element is on.
I check those at the moment the heat element cycles on and that should be close to the temperature of the eggs.

 

[Acornewell]

I'm racking my brain trying to figure this out. If you set on a Friday, and Hatch on a Friday (21 days) that could only be possible if you set on a Thursday?

 

[Yorkshire Coop]

I was very confused with this too when I first started hatching. But it is right because you count day 1 as a full 24 hours after setting. So if you set on a Friday say 10 am for example, day 1 is 10 am on Saturday and so forth. So day 2 would be Sunday 10 am. It needs to be a full 24 hours for it to be counted as a day of incubation. I hope this helps

 

[ChickenCanoe]

I was very confused with this too when I first started hatching. But it is right because you count day 1 as a full 24 hours after setting. So if you set on a Friday say 10 am for example, day 1 is 10 am on Saturday and so forth. So day 2 would be Sunday 10 am. It needs to be a full 24 hours for it to be counted as a day of incubation. I hope this helps

Well put.

If you set on Thursday, Friday will be one full day of incubation (24 hours), Sat. =2, Sun =3, Mon =4, Tue =5, Wed =6, Thur =7. For 21 day eggs, whatever day of the week, they're set is the day they should hatch.

 

[PD-Riverman]

I set my first set of eggs on the 29th of August. I set 13 eggs, which I gathered from my hens within 5 days of putting them into a stable incubator.

My first two chicks hatched on the 20th and 21st day. (I counted my setting day, as day 1) Once they were dry, I put them into the brooder. They are doing really well.

The third chick hatched late on the 21st day, and the 4th chick was pipped and working on hatching. I literally could no longer stay awake to watch the 3rd dry and the 4th hatch. I went to bed and woke up a few hours later and the 3rd was resting, but would wake up and chirp and then rest again. The 4th was further along, but not quite hatched. No other eggs were pipped at this point. So I dozed off on the couch right next to the incubator and woke up maybe an hour later and both 3 and 4 were dead.

I am absolutely beside myself. Trying to figure out if I did something wrong! They were alive. and not only did one die, but they both died.

I do not really have much hope for the remaining eggs. They are not moving like the others did.

You said that "Once they were dry, I put them into the brooder" Once you open the incubator to remove chicks that have hatched you "can" jeopardize the Hatch of the ones that have have not hatched yet. Do What you want but I would Highly suggest that you not open it till day 22 unless all the eggs have hatched before that time.

I threaten to Break a arm of anyone that tries to open my incubator before day 22 Unless ALL the eggs have hatched before that time. Even if a chick hatches early----say day 19, it will be Fine in the incubator till day 22.