Thank you. I should have read after the initial post. OP is in the state below me so I know it's cold there, but colder up here. Our 3-day-old chicks are in the house. I can't imagine trying to set them up somewhere else as it's been so cold, like tonight, 22F, but I suppose if there's a will, there's a way!The answer is in these bits:
The heat pad can provide one warm place for the chicks to sleep, and to warm up when they are cold. Having the rest of the pen at those temperatures can be fine for the chicks, but of course the water does freeze and that's what OP is trying to address.