molbert73 2,080 Posted September 9, 2015 It depends on the climate that you live in. I'm in Michigan so I have to bring my guys in for the winter where they reside in my 55 gallon tank. If The ground doesn't freeze you may be able to leave them out year round. 0 Quote Share this post Link to post Share on other sites
shakaho 6,312 Posted September 10, 2015 If I wanted to do this set up with 2 comet goldfish what would I do about winter? What climate zone are you in? NC ranges from 6A to 8A. If you have a basement, you can move the tank inside for the winter months. Two conditions can endanger your fish. If the pond freezes so hard that you can't keep a hole open in the ice, or if you have heavy snow, sleet, or freezing rain when the pond is not iced over. In the first case, the fish can suffocate from lack of oxygen if this goes one for more than a day or two. In the latter case, you can get slush in the water which has the fish at 32oF which can be fatal if it goes on long enough. Even if you are in the coldest part of the state you can protect your fish by building an insulated box around the tank. You can make a roof frame for the box which you cover with netting in the summer to protect the fish from predators and with plastic in the winter to make a "greenhouse." You can find a basic filter build here. 0 Quote Share this post Link to post Share on other sites