The pond that I am rebuilding had 40 gold fish, 5 Koi, 2 Slider Turtles and a bunch of crawdads. It ran like that for 9 years until a raccoon jumped over the fence. When the water gets to 55F stop feeding the pond, all goes into a type of hibernation. I remove the water pump tubing and keep it running so a part of the surface is not frozen. This allows the air to interact with the water so the fish have oxygen in the water.

It is currently warming up to warm 48.6F so there is not much ice on the small pond.

You can see the pump in the top left corner. It will keep the water from freezing most of the winter.

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