BRAND NEW AuqaShield 11 Watt UV Sterilizer Replacement Bulb Your First Line of Defense -Replacement UV sterilizer bulb - 11 Watt - for Auqashield UV 11 watt unit. -Comes with Quartz sleeve, 11 watt UV bulb, Filter sponge and Drop in cover. Cloudy water, Algae and parasites lead to the frustration of many hobbyists. The main reason why these problems occur is that each multiplies quickly; free floating in the tank, unseen to the naked eye. Only when it's too late, the hobbyist becomes aware of their presence. By adding a UV Sterilizer into your aquarium, you can minimize the risk of these problems occurring. Germicidal UV lights have been used for decades by the medical industry as a method for killing micro-organisms. This type of light has proven that it is effective in reducing the free-floating micro-organisms that pass directly through the light rays. The AUQA Shield harnesses the UV-C technology and encompasses it within a germicidal fluorescent lamp that produces light at a wavelength of approximately 254 nanometers. The infected water passes over the bulb, the wavelength travels through the water, penetrates the pathogens and mutates their DNA destroying their ability to multiply and after time will eventually perish. The AUQA Shield was designed to target free floating aquatic nuisances, by dramatically halting the spread of infections , saving your livestock from fatal health diseases, improving the clarity of your water and overall health of your aquarium. MidSize High Intensity 11 Watt UV-C Bulb Drop-In Installation (Overflow Column) Gravity Flow (No Pumps Required) Disposable UV Cartridge (Quartz Sleeve and Bulb) Quick Disconnect Mechanical Filter Sponge Realistic Wattage Rating Fits in ALL MidSize NUVO Fusion Aquariums