So for the last tree years that I have had my koi, I bring them inside for the winter. 1st year they went in my 60 gallon aquarium, last year I bought a 650 gallon pool. And this year I bought another pool ( the same one) cause I wanted to make sure there wasn’t going to be any holes in it from the storage. The largest one is about 1 1/2 ft and I have 3 koi and 1 gold. I live in buffalo New York. Our winters get cold 0-40 Some nights in the negatives. My pond is about 3 ft deep and about 1300 gallons. Next summer going to make it bigger and deeper!!! Well, I think they just moved around and or just gotten so much bigger from last year ( they still have plenty of room). That they disconnected my filtration system. Which I think was making some kind of noise under water. Which made my koi freak out. And two of them jumped out and died! I’m literally devastated. I’ve cried all day. I my friend came over and took care of it for me cause I couldn’t. I was so distraught. I called the pond guys about seeing how to put my remaining koi and goldfish back in the pond for the winter. They recommended a thermo de icer. I told them I didn’t really want that cause they’re extremely expensive to run. He said this one will only kick on when it’s under 35 degrees. I said okay, so that’s everyday. But he did say a 100watt soups work fine. And he said about a aeragation system. Please I need help. I don’t know what to do! What does everyone use outside to keep their pond from freezing? Should I re do my pond now for the winter. Idk.