TREATMENT OF KOI PONDS WITH A FLOATING BEAD FILTER AND ULTRAVIOLET LIGHT COMBINATION  

Floating bead filters are used with ultraviolent lights to clarify koi ponds.  Smaller ponds have traditionally been filtered with hourglass filters that provide nitrification and solids capture.   With more than enough nitrification capacity for the lightly loaded koi pond, filter sizing is based upon the turnover rate of the pond.   High water clarify is normally achieved with turnover rates in the range of 90-180 minutes, so a sizing criteria of 1 cubic foot of beads for each 2000 gallons of pond volume is used in practice.   The bead filter is complemented by ultraviolent light treatment to control growth of algae blooms (green water).  The UV light system should be have a capacity of about 10 watts for each 1000 gallons of pond.   The UV light are usually placed behind the floating bead filter.  Water is circulated by a how head submersible or self-priming centrifugal pump.   A water fall provides enough oxygen for a koi pond application.

Larger, deeper ponds can be filtered with a PolyGeyser filter sized to provide pond turnover every 3-6 hours.  The PolyGeyser filter is typically backwashed by a linear air pump eliminating the requirement for manual backwashing.   The PolyGeyser accumulates sludge that has to be removed about once a week.    The sludge make a great fertilizer for plants in the back yard.