golden 300 ducks hatch at 28 days. So that would put them hatching the 25, hopefully. if all goes well. Right now I'm going by ambient air temp of 99-100. I do have a water wiggle toy w/ probe but the temp for that fluctuates all over the place(don't know why but it does). Keeping my fingers crossed. Looking forward to have lil black n brown ducklings hatch on x-mas.