Pond filtration is an absolute necessity in ornamental fish ponds.  There are many different methods and styles of filtration, but there are three main categories that most systems fall into.  Mechanical and Biological filtration, along with Ultraviolet Sterilization can be a successful combination in any Koi Pond filtration system.  Most Pond Culturists are aware of the names, but few can describe the function of these essential components.

Starting with the most often used, Mechanical Filtration is a way of removing physical objects from your Koi Pond.  Most often employed in a mat or floss form, mechanical filtration is a major part of most commercially available filtration systems.  If custom built, a mechanical filter can be a simple filter mat places in-line with water flow.  This can be at the beginning of a water fall, in a submersible filter, or atop an overflow box.  However the mechanical filter is employed, it is imperative that the waste it collects be removed as soon as possible.  The idea behind mechanical filtration is that the waste be removed before decomposition into fertilizer for nuisance algae, or water-fouling bacteria.

Biological Filtration is a necessity in Fish Pond Culture.  Often employed unintentionally, biological filtration is the act of growing beneficial bacteria on a substrate.  This can be as simple as running a stream or waterfall over ornamental pebbles, or as complicated as some of the expensive sand bed filters or space-aged filtration material.  The most common form of biological filtration in Koi Ponds is most often referred to as “Bio-Balls.”  They are a simple plastic material most commonly in the shape of a round blue ball specially shaped for maximum surface area.  They are then places in a container which water is passed over.  The bacteria culture will then biologically clean the water that is passed over it, converting decaying matter from Ammonia to Nitrites and Nitrates.  With a properly functioning mechanical filter to remove most of the organic waste before it breaks down, the Biological Filter will provide a healthy environment for your Fish Pond.

Ultraviolet or U.V. Sterilizers are one of the most misunderstood concepts in Koi Pond Culture.  Often viewed as an expensive gadget unnecessary for the average Pond Owner, U.V. Sterilizers can be an integral part of any filtration system.  If properly constructed, a fish pond would be a balanced ecosystem, with enough plant life to utilize the waste produced by your ornamental fish.  The problem arises when most Fish Ponds are overstocked, at least to the point where the plant life cannot keep up with the organic waste produced from your fish.  This is where the Sterilizer comes in.  If left on its own, the extra nutrients produced would grow algae, creating beautiful, deep-green water where your crystal clear pond once was.  The U.V. Sterilizer neutralizes the algae before it has a chance to convert your backyard oasis, keeping the crystal-clear centerpiece you’ve worked so hard at creating.  It has the added bonus of eradicating parasites and other nuisances, such as mosquito larvae, found in the water column.