Cooling Fan with compact design and powerful performance, which is positioned above the water level to blow air across the water surface, thereby cooling the tank. Flexible arm feature for adjusting various angles and equipped with "clip on" feature for easy installation on most aquariums. Suitable for freshwater or marine aquariums, and even for pet use. Reduces the water temperature in a tank by up to 3 degree celsius. Air Volume generated = 18 cubic feet per minute.