They are majestic, but by no means easy to care for: for example, if the koi pond is not properly winterized, the joy of the animals can quickly disappear.
We probably don't need to explain to you why koi carp are so popular all over the world. Hardly any other fish impresses with so many different colors and markings as the Nishikigoi (literally "brocaded carp"). It is therefore not particularly surprising that more and more garden pond owners say goodbye to the goldfish and prefer to create a koi pond instead. Not least because the animals have something noble about them. They used to be considered status symbols by the nobility.
There is a small problem though: while koi carp are beautiful, majestic animals, they are not exactly easy to care for. And that in turn is forgotten by many and they get the animals without thinking about it. And that in turn often takes revenge during and after the winter. Because if you don't winterize your koi pond properly, don't be surprised if the animals don't make it through the cold season. So there are a few things to note here.
Tips for wintering koi carp
Kois are quite robust animals. For example, they tolerate temperatures of four to 30 degrees without any problems. However, you should know that water has its greatest density at a temperature of four degrees and is therefore also at its heaviest at this temperature. Accordingly, the warmest layer (four degrees) is at the bottom of the koi pond. And this warm layer must now be preserved. The following tips show how this works.
Tip 1 - keep a spot free of ice:
You should always keep one spot in the pond free of ice. This is intended to enable you to observe your koi in winter and treat them if they become ill. Keep part of the koi pond free of ice, also ensure that the fermentation gases can escape and gas exchange can take place.
In order to keep a spot in the pond free of ice, it is best to get a pond heater. You can buy such a device cheaply in different wattages from Schegoto buy. Alternatively, you can also rely on ice preventers made of Styrofoam. These work without a cable or pump and still effectively keep an area of the pond free of ice. You can get ice preventers made of styrofoam in different sizes for less than 20 euros.
Tip 2 - Cover the koi pond:
To prevent the garden pond from getting too cold, you should also cover it. Bubble foil, styrofoam or PE pond balls are best suited for this. The latter variant has the advantage that the balls let snow and rain through, do not fly away and do not impede gas exchange.
You can of course also combine several variants, e.g. if you don't have the possibility to store many PE pond balls. Then simply cover part of your koi pond with styrofoam and the other part with the PE pond balls.
Tip 3 - switch off/remove pond technology:
In winter, adjust the water inlet so that the water from the filter cannot flow into the deep region. This means that it cannot mix with the warmer water and the water current does not disturb the fish during their hibernation. Also, close the bottom runs and remove the pumps and fans from the deep region.
You can also switch off the UVC system or even remove it completely from the pond, since at water temperatures below ten degrees there is no longer any algae growth.
Tip 4 - Feed koi carp properly:
In winter or when temperatures are low, the koi's metabolic activities are reduced in order to save energy. Accordingly, you should or need to feed your animals only a little in winter. It is also important that you use food that is adapted to the temperature conditions. You can buy special winter food for this purpose that sinks to the bottom of the pond. This means the animals don't have to move around a lot and don't have to come to the cold water surface to eat.
Important: Do not startle the animals!
Never disturb your koi carp during their hibernation. Otherwise you could set off a chain reaction. For example, if you make loud noises, these can cause your koi to startle and move frantically through the pond, consuming a lot of energy and not surviving the winter.