OASE FILTOCLEAR 20,000 koi pond filter with built in 36 w uv clarifier. These are a very low maintenance and very effective filters .to clean the sponges all you do is pull up and down on the handle to agitate the sponges then turn the blue knob to flower position which empties out the dirty water and sludge. The 36 w built in uv clarifier will keep will keep your pond water free from green and keeps the pond water healthy. All in perfect working order and sponges are in superb condition. These filters can be partially buried to make them less visible
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