I'm sorry it's not going as planned. Please don't use the float test, it is not reliable, and it will drown your eggs. I once threw out a whole clutch of alive embryos because the float test was wrong and I wrongly trusted it. Is your temp definitely accurate? Do you have at least one calibrated thermometer in there? I would candle them again, and take pictures to post here. What day do they look according to this chart? What has your humidity been? Really watch each egg for at least 2 minutes. Tap the egg, talk to it, whistle to it, flicker the light, watch for any movement. Also, sorry about the questions but please try to answer them all, it will help us figure the problem out. Here's the chart. Oh, what kind of ducks are they?
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