18W 640GPH AC Pond AeratorPowerful Oxygenation for Large Ponds: With an impressive 640GPH (40 L min) air flow, this pond air pump quickly increases dissolved oxygen levels in ponds up to 3000 gallons, keeping your fish healthy and your water clear and fresh all year round. Ultra Quiet Operation for Peaceful Yards: Our pond aerator features a double layer sound insulation structure that operates at less than 45dB, quieter than a library, so you can enjoy your outdoor space