Filters are a great way to help keep your pond clean. There is a selection of pre-filters to give you more surface area to stop your pump from clogging up so often and a range of external filter, which is the best option for low maintenance. They work best paired with a Dirty Water Pump, which can take bigger particles through the impeller and straight through to the filter. There are two types, Gravity and Pressure. The Pressure filters are ideal for pushing water and can be hidden away easier then a gravity feed filter, that needs to be above the pond to feed back in. The filters can come with or without a UV light, which is the fool proof way of getting rid of that murky or pea-soupy green water that may form in ponds.