Hakko Air Pump HK40LP

Hakko Pond Air Pump is compact, affordable, energy-efficient and very, very quiet (less than 38 decibels. For outdoor applications, it is recommended that the unit be enclosed to protect it from the elements. This is an external air pump not to be submerged. Tubing (Not Included). The outlet fitting is approx 5/8" O.D.  

 
These air pumps can be used to create a large column of bubbles rising from the bottom of a pond or lake. It brings oxygen depleted water to the surface where the bubbles burst and create tremendous surface turbulence, circulation and aeration.