Emperor Aquatics SMART UV Lite Sterilizers 25W (Mfg# 2225) 25 Watt SMART UV Lite Sterilizer with 0.75" Barb inlet/outlets 2" Diameter body, and a single 25 watt uv lamp and quartz sleeve. The 25 watt SMART UV Lite offers a suggested flow rate of 332 GPH and a maximum flow rate of 554 GPH for ponds of up to 1,600 US Gallons Targets waterborne Algae and harmful Bacteria Great for Koi Ponds and Water Gardens