Overwintering Ponds & Pond Fish

The beauty and importance of ponds in landscape design and gardening are indisputable—from beautifying your garden to helping the local environment and wildlife thrive. But how do you maintain a pond over winter? The goal of this guide is to provide you with a checklist of everything you need to know about winterizing your pond and pond fish! 

 

Should I Remove the Water From My Pond for Winter? 

Your pond water does not need to be removed for the winter. Your pond’s ecosystem and fish will both survive the winter in your pond as long as there is an air hole on the surface and the bottom does not freeze. However, you should remove your pond pump! 

Mother Nature Garden Centre-Powell River-Overwintering Ponds and Pond Fish-removing pond pump

Removing Your Pond Pump 

The best way to prevent your pond pump from being damaged by freezing is to remove it from the pond—and clean it thoroughly before storing it for the winter. Pumps that operate directly (not magnetic drive or asynchronous) need to be kept in water safe from freezing temperatures. Seals are kept moist this way. As for magnetic and asynchronous pumps, any dry place can be used to store them. Upon the end of winter and the arrival of spring, your pump will be ready for installation again! 

Mother Nature Garden Centre-Powell River-Overwintering Ponds and Pond Fish-clean fish pond with net

Clean Up Organic Waste

Organic debris and other waste should be removed from the bottom of your pond. This will help maintain the quality of your water, and can be done easily by using a pond net or vacuum. In the winter, leaves, sticks, decaying algae, or plant material remaining in the pond will slowly deteriorate, consume oxygen, and impair water quality. After cleaning, you can place your marginal hardy pond plants back in. 

 

Cut Back Dead Foliage On Marginal Plants 

A hardy marginal plant (plants found growing around the edges or margins of your pond) can survive through freezing conditions. As long as you remember to cut the dead foliage back, the plant can be left in the pond through the winter. Iris varieties, sweet flag, rushes, reeds, grasses, and horsetails, are among the plants that fall into this category. Whether submerging them deeper or leaving them in their regular place, they should all survive just fine through the cold! 

Mother Nature Garden Centre-Powell River-Overwintering Ponds and Pond Fish-pond heater for winter

How To Winterize Your Pond Fish 

The winterization of your pond fish is crucial to their survival and to ensure a safe habitat throughout the winter. To overwinter fish in your pond, make sure the water is oxygenated, and the pond is deep enough not to freeze solid to the bottom. Fish should be overwintering at an average depth of around 120cm. Follow these other care steps to overwinter your pond fish:

  1. Check to make sure your pond and water features are clean and that you’ve trimmed back your water plants. 
  2. Install a pond cover net to trap organic waste and debris. 
  3. Ensure your pond fish can survive through Powell River’s winter temperatures. Hardy fish varieties include koi fish and goldfish. 
  4. Ensure the water has safe pH levels, ammonia, nitrates, and nitrites. Double-check that what you feed your fish is safe for them by verifying with your fish supplier. 
  5. Take out all pumps, circulators, bubblers, and filters—cleaning and storing in temperature safe-zones. 
  6. Keep a water area open by installing a de-icer or fish pond heater. During the winter, fish survive by maintaining a hole in the ice. This is needed to help oxygen enter the pond and expel noxious gases such as carbon dioxide. 
  7. Fish should not be fed if the water temperature drops below 10 degrees. When fish aren’t eating or moving much, their metabolisms slow down. Feeding them can actually do more harm than good in these situations, as they are mostly in a state of torpor. This state is when a fish’s metabolism slows down as their bodies conserve as much energy as they are able to. Most of the food they eat during this semi-dormant state will sit undigested in their stomachs, meaning you risk making your fish sick if you feed them after the water temperature drops.

Mother Nature Garden Centre in Powell River has the gardening expertise to keep your pond fish from turning into fish-cicles! Visit or contact us for more information on overwintering your pond today.