Winterizing Your Koi Pond

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If your water temperatures drop below 50℉ in the winter, you need to prepare your pond for the colder weather. If your pond is at least four feet deep in climates that regularly freeze and three feet in places with chilly but milder winters, it is best to leave your koi in the pond through the winter months rather than attempting indoor transport. They will be safe as long as you maintain the pond correctly. Here are some tips for getting your Blue Ridge Koi ready for the winter.

Clean out Your Pond

Use a skimmer or pond net to remove leaves and debris from the pond while they’re still floating on the surface. If left in your pond, decaying plant matter will cause oxygen levels to drop and toxins to build, both of which can harm your fish.

Treat for Parasites and Infections

Before temperatures drop, treat any possible parasites or infections. Consider a broad-spectrum treatment for various parasites. The koi’s immune system will shut down as it goes into a state of hibernation known as torpor. Though the parasites will become dormant, too, they will revive in the spring sooner than the koi and quickly put them in a very vulnerable condition.

Stop Feeding

Stop feeding when water temperatures dip below 50℉. Even if your koi are still active, feeding them at these temperatures can be dangerous. Koi cannot digest food once their metabolisms slow for the winter, so whatever they eat can become trapped in the intestinal tracts. If you want to ease them into their seasonal fast, you can begin reducing feeding frequency with a wheat-germ-based food designed for cooler water once temperatures fall into the 60s.

Install a De-Icer

If ice covers your pond for an extended period, toxic gases build and can rob the water of oxygen. A de-icer will create a hole in the ice that allows harmful gasses to escape and life-sustaining oxygen to enter the pond. Pairing your de-icer with an aerator will further push out gas while pulling in oxygen.

Use a Pond Cover

Installing a temporary pond cover or greenhouse can add a layer of protection from the elements. The cover traps heat and helps prevent the pond from freezing over. A strong cover can protect your pond from cold winds, snow, and even predators. However, netting is also an effective and more affordable option if your goal is to keep out debris and deter winter predators.

Shut Down Your Pond

Whether you should turn off pond equipment depends on how cold the climate is where you live. Temperatures that drop below freezing can damage pond equipment, so turning it off and storing it over winter is usually recommended. If you have multiple pumps, you may not have to stop them all, but make sure water does not move enough to disturb the fish in torpor. After stopping the filters, drain the water so they do not hold rot and sludge until spring.

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