I've always had tank heaters that float on top of the water. They do
prevent ice from forming on top of the tank. I did some rough calculations
in my head after my last e-mail and the # of calories to warm water up
was not that high - but the floating kind do ensure the horses have access
to their water all the time.
Teresa
>
> Being concerned for the welfare of my beasts. last winter I splurged
> (against my husband's best wishes) and purchased a tank heater. It was a
> fancy one that turns itself on when the temp goes below 40degrees. We
> argued for so long that the first freeze came and went before it was ever
> installed. Just to prove my point, I dropped an aquarium thermometer in
> the water close to the bottom. Well, cold as guess what!?!
> The water never got cold enough to turn the thing on, even when it had
> several inches of ice on top.
>
> Becky H
>
>