I have 28 eggs in the octagon 20. First shipment of 7 bantam, all air cells were detached. I let them sit for 24 hrs, no real improvement to air cells. After setting them, about 6 hours later, I rechecked and air cells that were moving around the whole egg, settled in the large end. By day 7, there is veining in all 7 eggs.
Second shipment of 13 eggs, all air cells were beautifully intact. I let these sit for 12 hours but with such beautiful air cells, set them after that. At the 7 days, I can see veining in all 3 silkies and 3 Orphingtons. 3 Ameracaunas are clear

and I cannot see anything but the air cells (with 2 flashlights) in the Marans

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