ZenBlue CUV-118 Pond and Aquarium UV Sterilizer/Clarifier with UV Bulb, 18-watt 18W UV Sterilizer Includes 3 Inlets/Outlets (One in/Two out or One in/One out) Easy Unscrew-release for Bulb/Quartz Maintenance Supplied with external ballast 1 Year Warranty (Bulb not covered in warranty)