Adjustable retrievable lagoon aerators are marketed in the U.S.A. by AerResearch, Inc. They consist of separate diffuser assemblies, un-attached ballast which sits on the floor, and an adjustable system to position the aerator between the ballast and the water surface. Characteristics include:

1. Does not require a level floor.
2. Pipe can be submerged to avoid exposure to wind, ice, ultraviolet degradation, and vandalism.
3. Aerators remain at the same elevation even if the water depth fluctuates.
4. Operators do not handle ballast when retrieving/replacing aerators.
5. Aerators can be replaced to original submergence after retrieval.
6. Aerators are easily replaced to original submergence after retrieval.
7. Aerators are adjustable vertically while operating.
8. Aerators are levelable from tip to tip while operating.
9. Can be easily installed with water in the basin.
10. Dead-man anchors and tethers to maintain position are not required.
11. A system to maintain tether tension to compensate for thermal expansion and contraction of the air supply pipe is not required.
12. Can be installed offset from the air supply pipe.