Suspended algae cloud pond water and germs or bacteria that cuase illness threaten the fish. The Eheim CLEAR UVC ensures highly efficient remedying of both problems: Its special UV-radiation targetedly fights what harms the valuable pond fish and contributes decisively to crystal-clear pond water.+ compact and strong UVC clarifier for garden ponds+ high-quality UV-C lamp with long service life included+ low energy consumption even in continuous operation+ housing made of shock-proof and UV-resistant plastic+ can be used with separately pump or in combination with Eheim pond filters PRESS or LOOP+ 7 years Eheim guarenteetechnical data Eheim UV-C Pond Water Clarifier CLEAR UVC-7:Pond size without fish: 7000 lPond size with fish: 3500 l+ Power lamp: 7 WPower unit: 9 Wpower supply: 220-240 V/50 HzCable length: 5 mDimensions (WxDxH): 132x263x129 mmtechnical data Eheim UV-C Pond Water Clarifier CLEAR UVC-9:Pond size without fish: 10000 lPond size with fish: 5000 lpond size with Koi: 2500 l+