While you could haul all your fish to an indoor tank for the winter, or buy expensive pond heaters to keep your pond warm, neither may be the right option for you. Today, our experts at Art of the Yard in Denver, Colorado will present a variety of economical ways for keeping your koi pond from freezing this winter. It just requires some thoughtful planning and a little effort.
First, let’s start with a few things that are good to know about your fish. Ice is not dangerous to koi. As long as part of your pond remains liquid, the fish can simply retreat to the bottom and live all winter. Usually, a pond between 3 to 5 or more feet deep will not freeze completely.
However, the ice does cause a problem in that the production of oxygen becomes limited and the expulsion of toxic gasses is harder because of the insulating ice layer. By keeping these 5 points in mind, your fish will easily survive the winter.
- Aeration: Installing a good aerator solves the oxygen production problem and the water movement even helps keep ice from building up. Plus, an aerator is much less expensive to operate than a pond heater.
- Ventilation: The aerator takes care of oxygen production, but you still need a way for toxic gasses to escape. You can easily solve this by ensuring there are a few holes in the ice from which air can escape. Removing all the ice in the pond isn’t necessary.
- Balance: Keeping the right balance is essential for helping your fish to survive. During the winter, koi and other types of pond fish go into a semi-dormant state in which they need less oxygen to survive. For this reason, you don’t want your aerator so strong that it overwhelms them. A gentle stream of bubbles is sufficient. If your pond is relatively deep (4 to 5 feet or more) put the diffuser at a point in the middle of the depth range, so the fish have the option of settling down deeper to less disturbed water if they choose.
- Ice: A couple of pointers about ice. You shouldn’t hit the ice to break it, as the impact could cause a shock wave that is damaging to your fish. Monitor your ventilation hole and clean out any ice as it forms, before it gets thick and difficult to manage. If you need to make a hole, use a kettle full of boiling water instead.
- De-icer: If you live in an exceptionally cold area, have a pond that isn’t very deep, or feel that your pond will freeze over completely, consider installing a de-icer. This device will maintain an opening in the ice for proper gas exchange during the winter months.
We hope these tips will help you prepare for keeping your koi pond from freezing in the winter. While we’ve already had some cold nights, it’s never too late to make a few adjustments that will protect your fish. And of course, if you have any questions or concerns, don’t hesitate to call us here at Art of the Yard in Denver. We’re more than happy to help and answer any questions you might have.