I don't have many hobbies other than the koi and goldfish in my small outdoor pond which is about 3 X 5 feet. I usually bring them indoors for the winter up here in this cold part of Michigan, but this past spring, I thought I would try them in the larger pond which is 30 X 35 feet. (Any large fish wintered over, would die because of the built-up gasses in the pond, so I knew I would have to do something if I wanted to keep fish in there throughout the winter months). The fish did so well, I kept them in there and decided I would have to winter them outdoors because there was no way to gather them up for indooor winterization. I did a lot of research to see what would be needed to keep them alive out there in the big pond during the winter while it was solidly frozen over. It was either aeration, a hole kept open for dangerous gases to escape, or a combination of both. I chose to keep a hole in the ice with the use of a pond de-icer which I purchased at TSC. The de-icer is about 7-inches wide, is round and the top is tough plastic, and it floats. (It also has a long 3 year warranty which is great). It keeps a 12-inch circle free of ice. It seems to be doing the job just fine as even on some below zero temps, I would go out there to check and I saw my fish swimming around near the de-icer (probably looking for the sun and some fresh air), looking very healthy. Now my mind is at ease.... I was a bit concerned whether the de-icer would hike up my electric bill, or not, but I barely see a difference in the amount of electricity used for the 1250 watt de-icer. Also, I had looked all over for a de-icer and found that TSC had a very well-made one for the least amount of money, too. My fish thank you and I thank you, too!

I live in Birmingham, AL and drove to Huntsville to buy this item because stores near me don't carry it. We have had two nights when it was cold enough to freeze and both times my 250 gallon Rubbermaid stock tank has frozen over completely. Both times the de-ices is frozen in solid. This tank is used as a pond is right next to and sheltered by my house. I am not happy that my fish are frozen in when I trusted this product to prevent it.