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How To Protect Your Koi Pond During Winter Months

By February 10, 2015March 22nd, 2022Ponds
Kissing Koi

Winter has officially hit in New Jersey. It’s time for humans to disappear into their warm homes and koi to sink to the bottoms of their ponds. Fortunately for us, we can turn up the thermostat, make a fire and grab a cup of something hot. But our fish rely on us for their care, comfort and safety, so during the cold, icy months between now and spring it’s our job to protect them.

That might sound like a challenge as the temperatures drop and the snow sweeps in but with a few simple changes to your pond routine you can keep your koi tucked snugly away until you can all enjoy the warm weather again. Be sure you’re following this winter routine and if you’re unsure about the best route to take, consult your landscaping professional. Better to be safe than end up with an empty pond come spring.

Use A Deicer

This is one of the most important things you can do to protect your koi during the winter. A deicer is a device that sits on the surface of your pond and keeps it from fully freezing over.

Why is this important?

Because a pond that is frozen over can trap carbon dioxide and other gases in the water, reducing oxygen and ultimately killing your fish.

A deicer creates just enough exposed surface area to maintain healthy oxygen levels and preserve water quality.

A deicer isn’t meant to heat the pond. In fact, the heat will dispense so quickly in the cold temperatures that it should have no effect on the overall pond temperature at all. It’s also not necessary to keep the entire surface of the pond ice-free. Even a small hole can protect your fish from toxic water.

Winter can be stressful on your koi’s immune system and a deicer can reduce that stress so they’ll be prepared to fight off common diseases that pop up in the spring.

Don’t Break The Ice!

Ok, so you don’t have a deicer and your pond froze over. Now you’re concerned for your fish and you know you need to do something. But before you head for a hammer or drill, stop!

You should never break through the ice on your pond’s surface. The shockwaves can actually harm your fish, especially as they lay dormant and unaware at the bottom of the pond.

So if you can’t break the ice, what can you do?

Try hot or boiling water depending on the thickness of the ice. You can pour hot water over the ice enough to open up a hole or hold a hot pot or kettle against the ice until you achieve the same effect.

Then hurry quick and get yourself a deicer before it happens again. Your fish will be ok for a few days under a sheet of ice but prolonged periods can have fatal results.

Do Not Disturb

During the winter, your fish will settle into the warmer water at the bottom of the pond and their metabolism will slow. They rest at the bottom of the pond where the warmer water collects and wait for spring while we sip our hot chocolates.

Cold water holds more oxygen than warm water and since the koi’s respiration slows in cold temperatures, they’ll need less oxygen anyway.

If you need to aerate the pond, use equipment that creates small bubbles at the surface and doesn’t disturb the cozy water below.

If you follow these simple tips your koi will be safe and happy and ready for you to enjoy when spring blooms again.