The Enviro ET Series air pump helps to increase the amount of oxygen in the water. Providing a clean, oil-free air source it is exceptionally quiet in operation, even when running continuously. The ET Series is easy to service with a competitively priced service kit and is also supported by our two-year warranty. With its weatherproof, robust construction it makes an ideal wastewater pump. Benefits & Features Robust and compact construction - weatherproof Green drive technology - energy efficient motors, low power consumption Ideal for large grow systems and koi ponds Supplied with a brass fitting Blue Diamond recommends servicing all pumps every 12 months