Pond Filters are the key to good water quality in your garden pond

There are many filter methods and types

Methods used in pond filters include mechanical (flushed through a sieve), biological (bacteria convert toxins and other chemicals) and Ultra Voilet (UV) light treatment to destroy algae.
Filters can be grouped into the following types each having different costs, installation and maintenance requirements.
Filter Systems usually include an UV Clarifier, filter and pump. Deciding on the correct system depends on the presence and size of fish as well as the size of your pond. These type of filter systems work with active biological and mechanical cleaning. This means that the filter must be continuously supplied with water - i.e. 24 hours a day.
Pressure Filters use mechanical cleaning within a closed system. The polluted water is pumped into the filter housing. Because of the working pressure it is possible to mount a hose on the filter outlet to supply a waterfall or watercourse elevated above the filter.
Flow Through Filters do not operate under pressure and are therefore able to use biological processes. They are often installed higher than the pond so that the filtered water can be re-introduced to your pond via a natural looking waterfall.
Skimmers remove debris that floats on the water surface of your pond. Leaves, dust and other pollutants result in pond water becoming saturated with excess external nutrients. If not removed you're likely to end up with murky water and algae forming. The surface skimmer has its outlet installed as a vertical pipe opening to the pond surface. It can generally handle variation in water level up to 3 inches and is often used as one part of a filter system. Another skimmer type has a large vertical opening to the pool surface and can therefore handle bigger variations in water levels.