Fluval FX UVC In-Line Clarifier. The FX UVC In-Line Clarifier quickly and easily connects to all canister filters to eliminate suspended algae for a clear and clear aquarium. With unique CCFL technology, the FX UVC bulb runs cooler to last up to 2X longer than traditional lamps. It attacks green and cloudy water by applying powerful, DNA-destroying light emissions at a precise 253 nanometer wavelength. This natural process is chemical-free and will not affect beneficial, surface-dwelling bacterial colonies that are already established. Say goodbye to cloudy and green water forever! Effectively eliminates suspended algae in the water column for a crystal clear aquarium Unique CCFL bulb technology runs cooler than traditional lamps to last 20,000 hours (over 2 years of continuous use). Also prevents calcium build-up on quartz lens (no maintenance required) Energy-efficient 6W operation for powerful water clarification with lower energy costs Chemical-free process does not harm beneficial bacteria in the filter Light indicator window provides visual confirmation when UVS bulb is operational IP44 certification safeguards unit against water ingress (splash-proof) Fast and easy setup with flexible mounting options - connects directly to FX output valve or horizontally/vertically on cabinet wall (universal mounting bracket included) Multi-directional operation - units works in either water flow direction (no need to switch existing filter setup) For use in freshwater and saltwater aquariums up to 400 US Gal / 1500 L Compatible with Fluval FX Series filters and competitive canisters (1" to 5/8" hose adapters included) Compatibility: FX2, FX4, FX6 Canister Filter / 107, 207, 307, 407 Canister Filters What's Included: UVC in-line clarifier Power supply 100-240V/24V Rubber elbow adapter Adapters for filters with 5/8" (16 mm) diameter hosing Metal hose clamps Mounting bracket and screws.