Pond pumps can be kept running through the winter in places with mild winters. In colder places, pumps are removed from the pond and stored safely until spring. Ice can cause serious damage to a pond pump and other equipment, so carefully research how deep ice tends to go in your area, and make sure that your pump isn't at risk of freezing as well. If you do decide to turn off your pump, remove it from the pond and store it somewhere in water that won't freeze, preferably indoors. This removes the risk of the pump drying out and it's rubber seals cracking and becoming unusuable.
Keeping your pond pump running may have some benefits. This keeps up circulation and provides the opportunity for aeration even in the dead of winter. However, evaporation still occurs even in the cold. Keep an eye on your water levels and add more water when necessary. Running a pump dry is one of the quickest ways to damage the pump.
