Suspended retrievable lagoon aerators are marketed in the U.S.A. by AerResearch, Inc., Parkson Corporation, and Environmental Dynamics, Inc. They consist of diffuser assemblies with attached ballast which hang beneath a floating pipe. The pipe also serves to deliver air to the aerator through a flexible hose. Sometimes the hose is used as the suspension device. Characteristics include:

1. Does not require a level floor.
2. Pipe is exposed to wind, ice, ultraviolet degradation, and vandalism.
3. Aerators move up and down with water depth fluctuations.
4. Operators must handle ballast when retrieving/replacing aerators.
5. Aerators are replaced to original submergence after retrieval.
6. There is typically no vertical adjustment.
7. There is typically no system allowing leveling from tip to tip.
8. Easily installed with water in the basin.
9. Requires extensive dead-man anchors and tethers to maintain the positions of the floating pipes.
10. Requires a system to maintain tether tension to compensate for thermal expansion and contraction of the floating pipe.
11. Can be allowed to move rather than adjust cable tension if the floating pipes are far enough apart.
12. Floating laterals and tethers limit movement of boats around the basin.
13. Most designs require a special floating work platform capable of lifting the floating pipe in order to access the aerator.
14. Cannot be installed offset from the air supply pipe.