8. Preventing Green Water with UV Sterilizers

Nothing spoils the appearance and enjoyment of a garden pond quicker than green, murky-looking water. Installing a UV sterilizer is the only guaranteed method for the complete elimination of the green water. This is caused by millions of unicellular, waterborne algae. Algae spores are persistent in the air, falling into the pond where they proliferate by rapid cell division. Nutrients from fish waste, decaying plant matter, and other organics inevitably present in ponds keep these colonies flourishing. Also, they promote the frequent appearance of algal blooms.

How do UV Sterilizers and clarifiers help green water?

UV sterilizers generate ultraviolet radiation of sufficient energy to quickly and effectively kill microorganisms, such as algae. With continuous operation of a properly sized UV sterilizer, your pond remains sparkling clear without harming fish or plant life. This killing power keeps your pond free of dangerous microorganisms. This can otherwise become harmful to your fish. Further, the units should be protected from direct weather effects, such as rain or freezing, but are designed for outdoor use. This is a valuable addition for the serious Koi keeper.

Moreover, most UV sterilizers can be installed in-line, either before or after the biofilter, after completion of the Nitrogen Cycle. It takes from five to twelve weeks to complete the nitrogen cycle. Also, once toxic levels of ammonia and nitrite have fallen to zero, a UV sterilizer may be installed. Finally, after healthy colonies of beneficial bacteria are established, it may be installed.

OASE UV Clarifiers

The Oase Vitronic UV Clarifier with a mounting bracket comes in three different wattages, and easily integrates into an existing or new pond system. They clean the green out of the water and the Vitronic 18-36 W are easy to install on the housing of the BioSmart 5000-10000 filters. With clear tubing adapters, they show that the clarifier is working and green water is nowhere in sight! Safe and easy monitoring of the UVC bulb with an indicator light gives you a visual function to check, as well. 

Vitronic 9 W UV Clarifier
suitable for ponds up to 2,500 gallons
Vitronic 18 W UV Clarifier
suitable for ponds up to 5,000 gallons, can be installed on BioSmart
Vitronic 36 W UV Clarifier suitable for ponds up to 10,000 gallons, can be installed on  BioSmart

The Oase Bitron C with high-quality workmanship cleans the green algae out of water with adjustable flow control that optimizes water flow through the UVC chamber. Bitron C has impact resistant plastic housing and a quick-release fastener for easy opening of the bulb housing. The use of high quality UVC bulbs guarantees a long service life and a constant effective irradiation capacity. In addition, the Bitron C has an automatic cleaning rotor that is continuously guided around the quartz glass tube by the water flow and prevents debris from settling into the quartz glass.  

OASE Bitron C 55 Watt UV Clarifier
suitable for ponds up to 18,000 gallons in conjunction with the OASE flow-through filters, ProfiClear and BioTec ScreenMatic.
OASE Bitron C 110 Watt UV Clarifier suitable for ponds up to 18,000 gallons in conjunction with the OASE flow-through filters, ProfiClear and
BioTec ScreenMatic.

Danner Submersible Ultraviolet Lighting

Danner has created completely submersible ultraviolet Clarifier/Sterilizers. They should be placed outside the pond, and the blue halo light confirms operation. The unique vortex flow design increases water contact time and includes 9000 hr lamp, quartz watertight sleeve, transformer, 18’ grounded power cord, and barbed intake and outlet. It is a great value along with ease of use

See all Danner UV Sterilizers

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