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Incubate with no water for first week to allow the eggs to lose some moisture and create an air bubble large enough for the embryo to have room to breathe and to move in the last two days before they pip the shell. They will break through the membrane inside and start breathing air if this space is to small. They will struggle and die on day 19 or 20 as the temperature needs to be lowered just 1 or 2 degrees to help them with hatching.

The humidity needs to be quite high on the last day to stop them sticking to the shell, as they need to slide around easily when cutting their way out.
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