Suspended algae cloud pond water and germs or bacteria that cause illness threaten the fish. The CLEARUVC 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. Pond size: 20000 Pond size with fish: 10000 Pond size with Koi: 5000 Power lamp W: 18 Power UVC W: 18 Power supply V/Hz: 220- 240/50 Cable length m: 5 Dimensions mm: 132x263x129.