How To Select Outdoor Pond Filters

Everyone enjoys a beautiful, pristine pond, but keeping your pond clear, your fish healthy and your plants thriving can be a challenge. Protecting your pond from things like harmful bacteria and pollutants depends on choosing the right filter for your pond. Whether your pond supports plant or fish life, you need to know how to choose a filter that best suits your pond’s needs.

Determine the volume of water needed to filter
For a circular pond, use the formula: “diameter X diameter X depth X 5.9. This formula will give you the approximate volume in gallons that can be used to select a filter capable of cleaning the same volume of water.

Decide what type of pond filter you need
There are three main types of pond filters: gravity, pressurized and biological. Gravity filters use gravity to pull water through a series of filter materials such as coal or gravel. Pressure filters pump water and force it through the filtration materials. Biological filters negate contaminants by injecting beneficial forms of bacteria into the pond.

Determine how much maintenance the pond filter requires
Some filters, such as pressurized or gravity filters, require ongoing maintenance as the filters become clogged. This means cleaning the filter or buying a new one. In addition, some gravity filters also require that you dig them out for cleaning, which requires a lot of hard work.

Phosphorus the type filter of your plant pond and marine life
Koi ponds, for example, will benefit from biological filters that eat algae from the water or clean fish scales. Cattle or fishing ponds with an inlet, such as a stream, can be filtered with pressure or gravity filters located at the inlet of clean water entering the pond.

Make sure the pond filter fits your budget
Small filters capable of filtering 500 gallons to 700 gallons of water cost between $35 and $50. Five hundred gallons may seem like a lot, but 500 gallons is a smaller pond than just a few fish. Filters for medium sized 3,000 gallon to 4,000 gallon ponds cost between $500 and $1,000. Filters for larger ponds range in price from $800 to $2,000.