Pumpkin spice lattes, scarves, leaf changes and the onset of fall mean only one thing – winter is coming. And living in Redmond, we all know snow and ice is on the way. It’s only natural to worry about your koi during these frigid months. After all, they are family. Fortunately, koi are adapt to dealing with colder temperatures and an icy pond. They have a couple ways of keeping warm in the colder months of the year.
Koi Are Ectothermic Body Regulators
Koi are ectothermic when it comes to regulating their body temperature. That means their internal temperature is regulated by the ambient temperature of the water. Essentially, ectothermic is the politically correct way of saying “cold-blooded.”
Since koi are ectotherms, their body responds differently to each season. You may have noticed that your koi are beginning to move slower than they were at the height of the summer. Since ectotherms don’t have to maintain a consistent body temperature in the way humans and other mammals do, they are capable of using at little as 10% of the energy we do. This means they will require less and less food as the temperature drops and when the water temperature reaches 50 to 40 degrees Fahrenheit, they stop eating altogether.
Pond Heater For Koi Ponds
During cold months, your koi will be dormant. In a sense, they will be in the fish form of hibernation with not much activity going on internally or externally. They won’t need much food or oxygen in the water and it is possible for koi to survive in an iced over pond. However, at Russell Watergarden we recommend you use a pond heater to keep the water from freezing. A pond heater will aid in gas exchange and keep the koi pond from freezing over in surprisingly cold conditions. Avoid adding salt to your pond since it will artificially lower your pond’s freezing point temperature and can harm your koi.