pond boss Medium Filter Kit with Pump is ideal for use in ponds up to 500 gallons (1900 liters). The kit offers a simple, cost efficient way to start a pond and comes with an ETL listed, energy efficient 320 GPH (1200 l/h) pump that circulates water. The patented sloped lid prevents accumulation of debris as well as two filter pads that collect small and large debris to reduce maintenance and increase pump longevity. Bio balls are utilized to provide more surface area to aid in growth of beneficial bacteria. It includes a waterspray nozzle head for aeration and decoration as well as a diverter valve so you can enjoy a variety of water displays.