Air sac question

[Th55]

im trying incubation first time now and am on day 15. I did a quick candle 2 days ago and one showed nothing, one showed like a tiny black embryo and the rest showed veins, dark and/or movement inside, but I don’t recall seeing an air sac on any of them.
I’ve been trying to keep humidity about 50, but have had trouble keeping it steady. Ive read keeping it too high will prevent the sac from forming. Should I lower the humidity to try to help develop the air sac until lockdown then pump it back up?

 

[Th55]

im trying incubation first time now and am on day 15. I did a quick candle 2 days ago and one showed nothing, one showed like a tiny black embryo and the rest showed veins, dark and/or movement inside, but I don’t recall seeing an air sac on any of them.
I’ve been trying to keep humidity about 50, but have had trouble keeping it steady. Ive read keeping it too high will prevent the sac from forming. Should I lower the humidity to try to help develop the air sac until lockdown then pump it back up?

 

[Th55]

I also noted none seemed to be at the same development stage. Is this normal. All but one went in at same time, I added one 20 hours later.

 

[Nicaragua]

Since the air sac is formed by evaporation, high humidity will slow down its development, try candling and drawing a line around the egg every week until lockdown to make sure that it reaches one third of the eggs volume by then.
I just hatched my first batch at the beginning of the month : for the four in the incubator I didn't add any water until lockdown to keep humidity around 45%, with the six under mama hen I only vaporized them with lukewarm water on day 21.

For the development stages I'm not quite sure, but the 20 hours delay on one makes a big difference at that stage.

Good luck and keep us posted

 

[Trish1974]

I've read the humidity you keep your incubator depends on your altitude...
that makes total sense.
I ruined my first hatch with too much humidity. The instruction manual that came with my incubator said to keep humidity between 45-50%, which I did, and going into lockdown my air sacs were the same size they were at day 7-10. Nine hatched out of 30 eggs . I'm lucky I got that.
I then started doing some research and I read humidity should be kept in the 30s.
My area stays humid May-Sept. I just put another 30 eggs in the incubator last weekend and didn't add any water. The humidity is staying in the mid to high 30s on its own. We'll see how this batch turns out.

 

[Th55]

Thanks, I got a better light and candled while it was still dark in my room. I can barely see the air sac but it is visible, feeling little better about that now.
The first pic was the one put in 24 hours later, looks like started development and quit. The last looks infertal to me?
There are 3 that are completely dark vs the 7 that show lots of veins. This is where I’m concerned about the development differences. I have a second incubator should I lockdown these 3 early?

 

[AquaDuck]

Thanks, I got a better light and candled while it was still dark in my room. I can barely see the air sac but it is visible, feeling little better about that now.
The first pic was the one put in 24 hours later, looks like started development and quit. The last looks infertal to me?
There are 3 that are completely dark vs the 7 that show lots of veins. This is where I’m concerned about the development differences. I have a second incubator should I lockdown these 3 early?

You're right about the first and last pic being dead. You can go ahead and remove those. In the 2nd pic you have a small air cell for day 15 but not crisis-level. You can lower the humidity down below 50 %, and also make sure you turn the eggs a lot, that'll help them reduce moisture.
I wouldn't worry about the difference inside the eggs, it could be hard to see development through egg color, the fetus can lay in different positions inside the eggs, and a bunch of other reasons. They look viable and healthy, and that's the important thing!