I was reluctant to purchase a heated waterer since I had a bucket that used to be in my horse's stall.. but wasn't comfortable sitting a 5 gallon bucket out there. It just seemed like a great place for a chicken to drown. So I took this: (mine is a good bit older but very similar) and put this upside down over it It covers the water-er tank about 3/4 of the way down. We've had some nights down in the low 20's and so far it's kept not only the tank but also the dish below liquid. Just tossing out another idea for the battle of frozen chicken water.