Climate Considerations

• There are basically two options you need to consider for the pond in the winter months. Leaving the waterfall run throughout the winter, or shutting it down.

  Running the Waterfall Throughout the Winter

  If the pump in your pond moves at least 2000 gallons of water per hour, the waterfall can run continuously throughout the winter. It will keep a hole open in the ice as well as help oxygenate the water.

  The primary maintenance responsibility is to ensure there is enough water for the pump to operate properly. You may experience more evaporation in the winter when you run the waterfall and stream due to the dry winter air. Ice dams may also form in streams and waterfalls which will divert the water over the liner edge causing major water loss. As a result from too much water loss in the pond, the pump may burn out. Automatic water fill valves and outdoor water spigots are usually turned off in the winter, making it difficult to add water in the pond when needed. Water would have to be brought out from inside the house using buckets of water or a hose. This problem alone is why many people decide to shut their pond down in the winter.

  While there may be more maintenance involved with running the waterfall in the winter, there is a benefit. Mother Nature creates extraordinary ice sculptures that result in some especially beautiful winter scenes!

  Shutting the Waterfall Down

  The second option is to shut the waterfalls down for the winter. This involves taking the pumps out, keeping the water oxygenated, and keeping a hole open in the ice for gas exchange in order to keep the pond critters alive and healthy.

  Pumps should be removed from the skimmer and stored in a bucket of water in a frost-free location. The water around the pump housing will prevent the seals on the pump from drying and cracking. Make sure you remove the check valve so that the water drains from the pipe and the biological filter. This will make the start up in the spring easier since the filter and pipe will not be solid with ice.

  To oxygenate the water, place a small pump in the pond about 16” deep and let it bubble to the surface of the water. This replaces the oxygen in the water that the waterfalls were creating during the summer. Since the water is colder in the winter, it holds more oxygen and therefore you need less oxygenation.

  Keeping a hole open in the ice will allow for gas exchange. Harmful gases are created when organic matter, such as leaves and other debris, in the water decays and that gas can build up under the ice if there is no hole for it to escape. In severely cold climates, the pump is not enough to keep a hole open in the ice, so adding a floating de-icer is best.

Debris

• Leaves and other debris in the pond are usually more prominent in the fall than any other time of the year. Even if you have a skimmer on your pond, you may be cleaning the filter daily and still not catching everything that falls in. Over the winter, decaying debris in the pond will add toxic gases in the water that can harm aquatic life. If the skimmer is not catching all of the leaves, take a fish net and scoop out the majority of leaves in the pond. In some extreme cases, adding a pond net over the top of the pond will keep much of the leaves from getting in. To ensure proper filtration, always make sure the filters are not clogged with debris and that the pump is getting enough water to it.

Plants

• Fall is the best time to take care of your aquatic plants. Make sure that you stop fertilizing your plants after the first freeze. This will help the plants realize that it's time to start going dormant.

  Trimming back hardy plants will prevent organic debris from decomposing in the water over the winter. Bog and marginal plants should be trimmed down just above the water level. If the plants are overgrown, this may be a good time to split the plants to help keep them contained.

  Hardy water lilies will overwinter in the pond without difficulty if they are planted 12 inches under the surface of the water or deeper. Hardy lily leaves and stems should be cut back, leaving approximately 2 to 3” at the base of the plant.

  Tropical marginal plants can be brought indoors for winter and grown just like any other indoor tropical plant. Make sure that the pot is placed in a saucer that holds water to keep the plant moist. Tropical lily tubers can also be stored over the winter or they can be treated as annuals and replaced each season. All tropicals should be removed from the pond, otherwise they will create decomposing organic waste.

Fish Care

• I’m pretty sure our number one question is “What happens to the fish in the winter”? This is a terrific question since there aren’t many people who want to deal with setting up a tank indoors and netting all the fish in the pond to keep them from freezing. As long as the fish are not tropical and you have at least two feet of water you can keep your fish in the pond over the winter! Two common pond fish, koi and goldfish, are hardy and will be able to survive the winter. All you need is to recirculate water for oxygenation and keep a hole open in the ice for gas exchange.

  When the water temperatures reach below 55 degrees, stop feeding your fish. The temperature of the water affects the fish’s metabolism. If you feed your fish when the water is too cold and their metabolism isn’t functioning optimally, you can make them very sick and could even result in death.

Filters

• Many pond owners wonder what they need to do with their filters in the winter. Remove all of the filter mats, media bags, filter racks, and any other biological media from the biological filter box. The filters should be cleaned off well and stored in the garage or shed. If they are left in over the winter, they may freeze solid making it difficult to start the pond up in the spring.