I want to thank all those who responded to my water tank problems.
Unfortunately the only suggestion that I hadn't tried was the plywood over the
top of the tank with holes cut for the buckets then remove the buckets after a
while. So I'll think I'll try that. I did notice another of the horses drinking
out of one of the tanks yesterday. That's 4 down and 3 to go. Maybe it's
time to take the buckets away again and dump salt on their food and see if they
will get desperate enough to drink.
When it comes to grounding Rubbermaid tanks I have always taken a heavy
copper wire attached to the grounding rod, wrap it around a brick and put it in
the bottom to the tank.