We purchased a home with a pond two years ago. The one-third acre pond is...

Asked August 21, 2013, 12:33 PM EDT

We purchased a home with a pond two years ago. The one-third acre pond is approximately 30 years old. This year we have experienced a great deal of fibratous mat type algae. We are using Cutrine and trying to "rake out" debris and scoop out the mats. This does not seem to be working very well. We need a consultation or suggestions

Lucas County Ohio freshwater aquaculture recreational pond management

1 Response

Hi,
Aquatic pond issues are difficult to answer without an onsite observation. There are many causes that may be contributing to your filamentous algae problem. First and foremost are nutrients. Often times algae issues are a direct result of excess nutrients in the pond. Examples of nutrients is runoff from adjacent turf grass, pumping water into a pond from a ditch, excess fish and waterfowl in pond, and any other source or combination of.

To control algae short term is by using some type of aquatic herbicide. However restrictions such as is pond used for irrigation or drinking water, will determine what herbicide products are safe to use. Is it used for swimming or other recreational purposes?

You mentioned use of Cutrine and raking. Is Cutrine the granular form or liquid and are you applying using labeled directions. Cutrine is a copper based product and is somewhat ineffective on some of our mat forming algae.
Another herbicide is Sodium Carbonate Peroxyhydrate (GreenClean, Phycomycin) This is a fast-acting algaecide with results noticeable within several hours in the form of algae discoloration from green to a whitish or cream color. Its mode of action is oxidation, producing 100 times its volume of oxygen. Green Clean also has no water use restrictions. As far as raking are you raking out and hauling away the algae or are you leaving it on the banks. If not hauled away from pond the next rain event will wash all the nutrients that were locked up in the algae back into the pond. As you can see this is a continuous circle of events. This fact sheet gives additional info on filamentous algae control using herbicides. http://ohioline.osu.edu/a-fact/pdf/A_3_09.pdf

Long term control includes reduction of nutrients, raking out and removing algae, and using herbicides as necessary. Another control option tool is using aeration of the pond, aeration alone will not solve problem, rather aide you’re other control options. This guide to pond management is an excellent tool for beginning pond owners. http://www.dnr.state.oh.us/Portals/9/pdf/pondmgt.pdf Please contact me directly if you have any additional questions or concerns. Craig Everett