I have to confess...I've never used a thermometer and I've never adjusted heat. I rig the heat lamp to one side of the brooder and they get close if they need it and they walk away if they don't, kinda like in the wild with a mom. I pamper them until they have adult plumage, then they gotta do...
I loved using hay for bedding, I used pine shavings and had no problem but I would go with hay every time. It forks right out of the brooder super easy and if they make a mess with water the hay drains and dries super easy, the shavings get wet and super matted down and slimy.
Ducks have...