View Full Version : Overwintering goldfish in Manitoba

07-01-2015, 03:10 AM
Hi, I'm posting this question on behalf of a friend who is looking at taking some fish her father in law is no longer able to look after.

She has no space in her smaller home for a tank large enough to over winter indoors, and was wondering if they could survive outdoors through a Manitoba winter..
We'd thought we could use an air pump to keep things oxygenated and perhaps even a cattle trough heater to keep things from totally freezing up. She will also be building a pond for them, so we could probably insulate the sides of that too..

Does anyone do this, or are we just plain nuts? :lol:

Thanks in advance,

07-01-2015, 04:26 AM
Have a look through the pond forum. There are a few guys that keep their fish in the pond all winter long and they employ various strategies. You are on the right track with the trough heater although that may be wicked expensive to run over the winter. Keeping an air stone is a good idea. You could always try to keep the water moving with a magdrive (or similar) pump near the surface. A pond deicer is also a good idea to help keep a hole in the ice to allow gas to escape over the winter. Any gas trapped under the ice will most definitely kill all your fish.

07-01-2015, 04:45 AM
My pond at my previous house was used to over winter my goldfish and koi. I just made half of the pond 3+ feet deep and this is usually enough to prevent freezing to the bottom in prairie winters. None of my fish were big monster so I never used any pumps or airlines but it doesn't cost much to run an airline all winter to keep the water oxygenated.

07-01-2015, 05:20 AM
Probably doesn't get as cold here but - I just pull pump & filter out , let pond freeze over . Fish hibernate, ice forms barrier from weather & will insulate fish if deep enough. Don't keep water moving , otherwise water temp will drop lower than 0 & not freeze . Just make sure pond is deep enough to get warmth from under ground surface . Mine has only frozen 6" & is 2' deep , -15c

12-14-2016, 02:05 AM

Has anyone overwintered Koi in the pond in Manitoba? Mine are getting to big for the house. My husband is not really that fond of my fish so he didn't like the idea of an indoor pond. I thought it was a great idea.