Everything You Want to Know and More About Pond and Lake Aerators

The choice of an aeration system seems like an arduous decision, yet it can be made much easier when you understand the features and benefits of each type of system along with the dynamics of the pond or lake to be aerated.  With most ponds and lakes being man made storm water basins, the challenge becomes even more important for us to become better stewards of the environment and think long term with our aeration solutions.

There are three basic types of pond and lake aerators: surface spray aerators, air diffused systems, and horizontal mixers.  Each type has unique differences and efficiencies which can be utilized in several ways to achieve maximum benefit.  Ultimately, aerated healthy water is the desired result, however the size, shape, depth, and lake characteristics all play a part when choosing the best aeration system.

Surface Spray Aeration

Surface spray aerators provide the best circulation in waters that are 10 feet or less.  They provide “top down” aeration that breaks up thermal stratification, mixing the cool bottom waters with the surface. The wave, wind, and rain action created by the spray pattern not only exposes more surface area of the pond or lake to the atmosphere for oxygen transfer, but the agitation is excellent for breaking up algae mats as well as discouraging insect breeding in stagnant water.   A good surface spray aerator will have a minimum flow or pumping rate of 400 gallons per minute and have a strong oxygen transfer rate of at least 2lbs per hour.

Surface spray aerators are often categorized as fountains.  True, a floating surface spray aerator may have a “fountain” like pattern, but the characteristics between an aerator and fountain couldn’t be any more different.  A surface spray aerator’s main function is to provide oxygen to water.  Its second importance is to provide circulation and mixing thus, the high pumping rate.  A surface spray aerator is “aerobic exercise”; it’s like putting a pond on a treadmill, the more you work the water out the healthier the pond becomes.

A fountain is the contrary—by capping off the high pumping rate and channeling the pressurized water through various chambers or nozzles you get decorative patterns.  Any time you break the surface tension of the water, such as the splashing of a rain drop or the wave-like action created by wind you will achieve oxygen transfer, so a fountain will have some aeration qualities.  However, a fountain’s Achilles’ heal is its low pumping rate rendering it inefficient when it comes to beneficial aeration for lakes and ponds.

Air Diffused Systems

Air diffused systems, commonly referred to as “bubblers”, are most effective and efficient in waters that are deeper than 10 feet.  The deeper depths lend to more efficient lift and mixing from the micro bubbles emitted at the pond or lake bottom. As the bubbles rise through the water column at about a foot per second, they entrain or lift the bottom waters to the surface creating a confection current.  Diffused aeration systems are best used for their “bottom up” lifting abilities bringing the cooler dense bottom waters to the surface and exposing it to the atmosphere for oxygen transfer.  Their efficiency and effectiveness are greatly reduced in shallower applications and need to be properly sized to achieve the maximum benefit and results.

Horizontal Mixers

Horizontal mixers are best suited for ponds and lakes that are from 3 to 10 feet deep.  They are a very effective choice for those applications when a spray pattern is not desired, but a strong directional flow is needed.  They are a great choice for long narrow ponds or canals and are very efficient in breaking up algae mats and deterring insect breeding in stagnant waters.  They can be either floated on the surface or installed on the pond’s bottom orientating them in such a way to get maximum influence.

Like the saying goes, “there are several ways to skin a cat”, so goes it with pond and lake aeration.  As long as we are environmentally conscience with our aeration solutions, then there really is no wrong way to give Nature a boost.