I bought eggs off ebay and almost all were fertile. Those that were developed nicely up to about day 14. Some quite before that. At day 17 I checked them again and all but 3 seemed way under developed. Like they never got past day 12 to 14. No movement or life it seemed. On day 18 just before I locked down I was able to see 3 chicks moving. One egg was almost completely black (that is what you want right?) and the other two were alive but seemed to be much further behind. I saw them moving around in there though! One has a strange air cell, like it is on the side sorta. So-I'm on day 23 and still nothing. I've got constant temps and my humidity is up around 70-80. Any thoughts on how long to let them go? Should I check them? This is my first hatch so any advice would be awesome! Thanks!
Personally I would check them / candle them. Open the incubator as little as possible and do the sniff test - if they smell, get rid of them quickly. Handle them carefully, they may explode if rotten. I have had that happen. I am hoping for you.
This may only be me, but at this point I would quickly open the incubator and candle an egg or 2 to see if anything is going on. You should see something. Usually when they are ready to hatch the egg will be all black but you will see movement near the air sac.
I did throw out all the under developed ones before I went into lockdown. All I have left in there are the 3 I though had a chance. I did sniff them today. No smell.
Congrats! Sometimes they can be a bit slow, day 23 is pretty late though, so I'd check thermometers and dates to make sure it's not really half a deg low or a 24 hr cycle off. Even so, it could be that this strain is a late hatcher. I've had some as late as day 24 make it.