I have a small pond and it is not very deep I don't think it is even 2 ft deep. Well I am trying to keep a hole in the ice, because I have a frog in there that started as a tadpole. I really don't won't it but I am trying to keep it alive. Well next summer I would like to get a pond heater or somthing to keep the water cold for my goldfish. Well could anyone tell me of a cheap brand of outdoor pond heaters or how I could make one.