Seven out of a dozen are left. one was cracked and started to smell funny so it went on day 3. One had a crack but didn't stall until sometime between days 6 and 9, I left it in until day 12 then removed it as there had been no growth. Two were growing in fits and starts and one had some embryo growth but no air cell, so they stayed in until lock down. The seven that are left were all wiggly when I checked them on day 18, they also had good air cell growth. I'm now obsessively checking the incubator for signs of peepers!