Day 29 silver apple yard eggs. Day 28 could hear tapping/pecking and seen egg movement. Today absolutely nothing and had a temp drop last night.

[New duck mommy 2021]

The third when I candled it seem to have stop developing some time ago, for a lack of a better description it appeared to be more red and had floating parts.

Most likely did stop
I hope you get a better batch next time
I run my first 25 days at 45-55 humidity
And have had Perfect air cells then 65-70 last 3 days
I also take mine out of bator 5-10 mins once a day and mist them with warm water from days 10-25
Humidity also depends on your climate
If you are really humid some run lower then me and really dry they run a bit higher.
Don’t be afraid to try again
You know a lot more now and will get little ones