Goldfish and koi can survive winter outdoors so long as ponds don t freeze completely freeze solid.
Outdoor koi pond in winter.
That leaves 16 for the fish to lounge around and basically hibernate over the winter.
21 c or they may be stored as a dormant tuber.
They can survive water temperatures as low as 0 c which means they can survive in the pond during the winter as long as it doesn t freeze solid and they have adequate water quality and oxygen.
In the wintertime when the water in your pond is ice cold the koi fish s metabolism slows down to a crawl.
They spend most of their time treading water at the bottom of the pond while sometimes swimming around a bit.
If you simply make sure that your pond is at least two feet deep the proximity of the earth to the pond s surface will not allow the latter to freeze any deeper than 8.
They don t sit completely still all winter they need a little movement to keep their joints from seizing up.
The basic principle for winter pond care is as long as the water is circulating and there is an air hole to allow oxygen in and gases out fish and plants should be fine.
Goldfish and koi are very hardy fishes.
To help ensure healthy fish in the spring follow these steps.