I just hatched one that a friend brought by because a racoon got mom and most of her ducks. I had two that looked to be around a week. Yes, we were guessing by candling how far along they were, and the time my friend thought she had started sitting. We were close. I candled around day 18 and saw shadows in the bottom of the air cell..so into lock down the went. Only one made it. Soo cute..wishing I could keep ducks! Anyway, do your guessstament..then candle around what you think to be day 17 or 18. There are charts galore on google to help you see where abouts they are. Good luck. I have to share a photo of one of the candling I got. I love it when I get chick feet to show up, but this was new to me, and sooo cute!
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