Feature: -UV-C sterilizer helps neutralize harmful micro-organisms and free-floating algae -Preassembled aquarium UV sterilizer requires no additional pump or plumbing -Built in UV-C lamp ballast and single power cord mean streamline and clutter-free installation and operation. The newly designed pre-filter and quartz sleeve simplify routine maintenance necessary for optimal UV performance. -The amazing, submersible Submariner UV sterilizer/clarifier allows simple and effective UV control. Compact and versatile units are ready to install - no additional tubing or circulation pump required! Large mechanical pre-filter sponge captures debris to optimize UV exposure and built-in pump directs waterborne organisms past the UV-C lamp for clean, clear aquarium water. Install in vertical or horizontal position right in your aquarium or sump. Great for both fresh and salt water aquarium.