We've always used floating tank heaters. They do prevent ice from
forming on top of the tank. I have no experience with submersable (sp)
ones. I did some rough calculations in my head and the # of calories
to heat 10 gal water the 10 degrees a tank heater will add was not that
much (less than .5 mcal) but I think horses drink more if the water is
not too cold, and of course it takes a HUGE # of calories to melt snow
into water, so it is very important that a tank is not allowed to freeze
thick enough that they can't break the ice (or that you maintain a hole
in the ice for them)
Teresa
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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
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