Having had awful cockerel ratios this year, I've just put the incubator on again for a last hatch. We've also had poor hatching this year including a lot of dead chicks late on. I suspect they couldn't pip due to either dry shells or weakness. Anyway, I've dug out our old moisture meter and it's reading 30. I note the Brinsea manual says 40-50 for incubation. We don't normally put any water in until lock down but now I'm wondering if it's been so hot and dry this year that we have been incubating with low humidity. Should I put some water in now to raise it up?