So it’s your first year with a fish pond? All the excitement of setting up your pond and filling it with fish was great in the warmer months — but now it’s cold, winter’s setting in and you’re wondering how your fish will survive the frigid months from now until spring. Don’t worry — there are ways to help your fish survive these cold months. These four tips can help you get your pond and fish ready for the winter freeze.
De-ice the pond
While most ponds that are less than 3 feet deep won’t freeze all the way through, even a layer of ice on the surface can trap potentially harmful gases in the water and keep oxygen from getting in. If the gases can’t escape and fresh oxygen can’t get in, the fish will suffocate and die.
There are a few ways you can combat this problem. First, you can create a hole in the surface of the ice by pouring hot water in one section of the pond or by placing a hot pan of water on the surface of the ice. The hole needs to be about 12 inches across and it should remain open all winter long. Keep an eye on the hole to be sure it stays open and to see if the fish are swimming near the hole. If it doesn’t seem that the fish are near the hole, you should make it a little larger.
A floating de-icer can also keep an air hole open and requires less maintenance on your part. The unit has a heating device that keeps the area directly around the de-icer from freezing. It doesn’t keep the entire surface of the water from freezing and does not heat the water for the fish. If placed near plants with underwater roots, the de-icer can keep the plants from freezing over.
A pond aerator is another way to keep oxygen in the water. Pond aeration creates a current that produces rising bubbles to prevent freezing and promote circulation. You can also use a pond heater with a pond aerator for best results.
Check your filters and pumps
Most pond filters and pumps will not operate in extremely low temperatures. Check the paperwork that came with your filters and pumps to find the lowest possible temperature at which it will operate. When the temperature dips below its suggested lowest operating temperature, you’ll need to turn it off or it could freeze over and stop working for good. If your filters and pumps can run all winter long, be sure that the pump is pulling up warm water to the surface instead of pushing cold water deeper. It’s best for fish to congregate in a warm area near oxygen at the surface.
Bring tropical plants indoors
If you have tropical potted plants in or around your pond, you’ll need to bring them indoors to keep them alive for the winter. But, plants like water lilies that have underwater roots can survive the winter outdoors. When you remove your tropical plants, also clean out the pond and make sure it’s clear of sticks, twigs, leaves and other debris.
Keep debris out of the water with netting
Once you’ve removed all the debris from the pond, you can place netting or screen over your pond to keep additional debris out. Stretch it tightly over the surface of the pond and secure it with rocks or bricks. You can also put down wood or PVC piping before stretching the netting over the water to keep it from sagging down in the middle. Check the netting a few times throughout the course of winter to be sure it’s still in place.