For the question of winter watering of horses on acreage - I use a 100
gallon RubberMaid tank with a submersible heater that has a cage around it. The
heater sits on the bottom of the tank. At one time I had the tank against the
side of the building, ran the cord through a hole in the building just big
enough to get the plug through. A friend built a wood tank cover that covered
half the tank, held on by C-clamps so the horses couldn't reach the heater if
the water was low (heater has automatic shut-off if water level drops below it).
I also wrapped a small amount of barbed wire around the cord where it came
through the wall to the tank, there was a whole 8 inches of cord but my mouthy
Morabs wouldn't leave it alone. Now the tank fits under a fence panel with a
little less than half on the horse side and the heater AND cord are on the other
side, inside the building. Never took the temperature, but horses have
never had a problem drinking. Also, heater is attached to appropriate grounding
so it cannot short out in the water (don't ask me the mechanics - just know it
was done properly!)
