I was raised, without heating, and lived safely. It has been said that this kind of fish is dangerous when the water temperature is below 5 degrees, but it is unique to the south. It is seldom so cold in the south. Although it will freeze to death in winter in the wild, it is a dry pond, because water shortage is easily affected by temperature. This has never happened in a deep-water pond. The water temperature at home should not be so low. But if you like, you can heat it, so that the fish can eat normally, because when the water temperature is lower than 15 degrees, the turtle will reduce its food intake.