Repeatedly we will have pond owners contact us about a pond algae treatment that failed. We start all of these conversations in the same way… We ask them what they have growing. The pond owner will often say algae. What pond owners don’t realize is that all pond algae is NOT created equally; different pond algae require different types of algae treatment. Having trouble identifying your pond algae? Check out our pond plant ID page for additional help.
Here are some of the most common groups of pond algae: Planktonic, Filamentous, and Chara. There are specific types of algae that fall under these groups. Most types of algae are identified by a common or slang name.
The following types of algae fall under Planktonic: Euglena (red algae), Blue-Green (toxic algae), Oscillatoria, and Green Water. Planktonic algae is known for changing pond water color to green, brown, blue-green or even red! Planktonic algae are usually microscopic in nature and may not take on any type of form, therefore, this group of algae can’t be manually raked or removed except for Oscillatoria. Oscillatoria collects in the form of a mat on the pond’s surface but looks like snot and smells terrible! Planktonic algae is usually the result of excess nutrients and lack of other plant competition. A liquid copper sulfate like Crystal Plex is the only type of pond algae treatment that will control these types of pond algae. Granular copper sulfate will not affect algae from the Planktonic group.
The types of algae that fall under the Filamentous group are Horse Hair, “Moss”, and Algae Mats. The common names of these types of algae tell you a lot about how filamentous algae can be identified. Algae within this group is usually very thick and will form in mats on the pond surface. Once removed from the pond it tends to feel dry and coarse. Filamentous algae is extremely common and fairly easy to treat. The use of granular copper, liquid copper, or a combination of both have been used to effectively treat pond algae.
Chara pond algae virtually stands on its own in a group. There is one other type of algae that we classify with Chara, Starry Stonewort. Chara is interesting because it is frequently misidentified as a weed. It appears to be rooted, has a stem, and resembles a weed more than an algae. Chara grows in big billowing puff on the pond floor and once thick enough they can breach the surface of the water. This growth has a crunchy texture and a musky odor. A byproduct of Chara is usually an extremely clear body of water. Chara is a filter algae and we highly advise keeping a chunk of Chara to ensure your pond water remains clean and clear. The most effective pond algae treatment is liquid copper sulfate or Crystal Plex. Granular copper will not treat Chara. Late in the season the algae will become calcified and treatments will be ineffective.
Still having trouble identifying the algae in your pond? Take a picture of it and send it to us. We will do everything we can to identify the growth and point you towards the best pond algae treatment.
Next Monday we will release Part 2 of our Pond Algae Treatment Series: When Do I Start Pond Algae Treatment?
Part 1: Different Algae Require Different Pond Algae Treatment (Current Blog Post)
Part 2: When Do I Start Pond Algae Treatment?
Part 3: Will Pond Algae Treatment Hurt My Fish?