The most reliable UV we have ever sold! Backed by Laguna's Clear Water Guarantee. For ponds up to 1000 gallons, kills green water, parasites and harmful bacteria, making pond water cleaner, clearer and safer for all pond inhabitants. Maximum flow rate of 500 GPH. Click fit connectors make installation quick and easy with 3/4", 1" or 1 1/4" hose. 16 foot power cord.