Koi in the winter
Question:
I live in Pennsylvania where the winters get to mostly in the 20’s sometimes much colder. I’ve had ponds in the past and Koi did just fine. Is it true that they go “dormant” in the freezing weather/water? My brother does not believe that the Koi survived the winter and came “back to life” in the spring. I had some Koi that lived through years of winters. Can you clarify for me?
Answer:
We tend to say that the fish “go dormant”, but it is not quite correct in the true sense of the word. What happens is that their metabolism slows down due to the cold temperature of the water they live in. They never go completely dormant…you will see them swimming around occasionally. For this reason it is important to feed them good quality cool weather food in the fall to both allow them to store food reserves in the form of fat and to aid in digestion because their slower metabolism cannot process summer foods any longer. It is equally important to provide adequate oxygen and to make sure there is a hole in the ice that may form to allow harmful gases (carbon monoxide) to escape.