There is a common misconception that many pond owners help perpetuate, and that’s simply that pond aeration can stop algae growth. This statement, indirectly, has some truth to it, but generally speaking simply getting an aerator in your pond may or may not help with algae problems.
One can’t blame a happy pond owner when they finally see an end to their algae issues following the installation of an aerator. It’s happened more times than I could count, and therefore, it’s assumed that the aeration system directly reduced the algae bloom.
What really happened however is that by adding some aeration to the pond, and this could come in the form of a surface fountain, or a submerged diffuser, the pond’s environment was improved (most notably dissolved oxygen increased) and any existing aerobic bacteria started to perform a bit better.
This stimulated bacteria and microbes begins to out-compete or reduce nutrients in the water that the algae will feed on and because this bacteria is aerobic, it will perform better in well oxygenated conditions. The reverse is true as well. In very low oxygen, the bacteria simply can’t function very well and it begins to slack in it’s attempts to keep the pond more clean and balanced.
When someone comes along and installs a pond aerator and they see this reduction in algae growth, it can pretty well be assumed that there’s some remaining bacteria present in the pond. When an aerator is installed and you don’t see improvements after a period of weeks, then it’s possible that the bacteria numbers can’t recover without some supplementation. Adding a beneficial bacteria to the pond will often improve things and the goal is to supplement for a few months, then allow the ongoing aeration to maintain a level of balance.
Be sure to visit the following link to learn more about the various pond aeration systems for any size of pond.