What should you do when the weather gets colder? Use a koi pond heater or a koi pond de icer? The answer is “it depends”.

As long as your pond is deep enough you can keep your koi outdoors through the winter.

Their metabolism will slow down and you’ll need to switch them to a lower protein food in the fall and then stop feeding them altogether once the temperatures drop below 50 degrees fahrenheit.

At that time they will become very sluggish and hang around at the bottom of tthe pond where the water is warmer.

The reason some people like using a
koi pond heater is because they like to feed their koi through the winter. When the fish are not taking in nutrients and are sluggish their immune systems slow down as well.

Then in the spring when they “come back to life”, other things, like bacteria are coming back to life as well. With their suppressed immune systems your koi are more susceptible to bacterial infections.

Many people prefer being able to feed through the winter to having to treat their fish for a bacterial infection.

If your pond freezes over in winter you will need to make sure to keep an opening in the ice for gases to escape. If gases get trapped beneath the ice you will end up with a pond full of dead koi in the spring!

A de icer will keep a small area open on the surface of your pond, allowing it to “breathe”. You should NEVER open a hole in the ice by breaking it with a hammer or other implement as this will send shock waves through the water that can kill your fish.

If you live in a colder climate you need to decide if you prefer to use a koi pond de icer or a koi pond heater.

Alan Deacon

KoiCareBasics.com

In the fall when water temperatures fall to 50-60 degrees, you should change your feeding schedule to once every 1-2 days.

A low protein food should be fed. Many companies make special foods for spring and fall, when you are switching from feeding to not feeding.

When the temperatures drop to below 50 degrees you need to stop feeding the fish altogether.

In the colder temperatures the metabolism of your fish slows down and food cannot be properly digested. It can take up to 3-4 days for your koi to fully digest their food.

Don’t be fooled on warm days when your fish may become active and “beg” for food. Stay strong and do not feed!

If your koi really do need a little food, they will find enough growing in the pond. The algae that is still coating the pond liner more than enough. You don’t want to literally kill your koi with kindness!

Koi fish food definitely needs to be fed according to temperature. In many parts of the country, temperature coincides with the season, which is why you hear that koi need to be fed according to season!

Alan Deacon
KoiCareBasics.com