Planted or ornamental pond with no livestock
You do not need to have the equipment running throughout the winter as the bacteria that process pond waste starts to die back once the water temperature reaches 10°C.
If you do keep fish in your pond, you will need to consider how cold the winter tends to be in your area. If your temperatures normally remain above freezing, then you may prefer to keep your equipment running throughout the colder months. Make sure you decrease the flow rate and move the pump away from the bottom of the pond.
If the winter temperatures in your area tend to be freezing disconnect the pump, filter, and UV clarifier before water freezes. Make sure your equipment is drained of any water and that you’re filter and media is cleaned before starting back up in the Spring.