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How To Control Filamentous Algaefilamentous algae

While there are a wide assortment of invasive aquatic weeds which can grow on a pond or lake, perhaps none is more hated aesthetically than filamentous algae which is also known as “moss”. Filamentous algae is also lovingly known by other names such as “pond scum”. Filamentous algae is highly noticeable in ponds and lakes, characterized by bright or dark green hair-like mats which accumulate in the water and float on the surface of the pond resembling wet wool.

Filamentous algae comprise of are a series of cells joined end to end which resembles a thread-like appearance. The growth of filamentous algae often begins at the bottom of a lake or pond and then rises to the surface as oxygen becomes trapped by the filaments. Often times this type of algae will "disappear" after several days or immediately after rain events when trapped oxygen is allowed to escape. This "disappearance" lasts for only a short time until oxygen once again becomes trapped.

High levels of nutrients in the water can cause algae abundance to explode, especially in ponds lacking other aquatic plants, becoming so abundant that severe oxygen problems can result in the summertime especially in the early morning.

Filamentous algae ruin recreational activities like swimming and they provide nearly no value in recreational ponds. If you have a problem with filamentous algae on your pond or lake, you can eliminate the “pond scum” using aquatic herbicides from Solutions Pest and Lawn

Browse our filamentous algae control products below. If you need any assistance with your order or any DIY advice, you can contact us directly via email, live chat or by phone and we will be happy to answer any questions you have.

How To Get Rid of Filamentous Algae: 3 Step Solution

Removing filamentous algae from an area where they have accumulated can be rather difficult especially if they have reached abundant levels on a surface. You can perform mechanical control by raking the algae up in clumps with a rake. However if you have a large pond to deal with and a lot of algae, this could be a long, tedious task that will take up a lot of your time. That is why we suggest a chemical method of control using aquatic herbicides. Below you will find a simple 3 step program to tackle nuisance algae the DIY way.

Step 1: You should start the filamentous algae removal process by first carrying out a careful inspection and analysis of the body of water that will be treated for aquatic weeds. It is important to take into account the fishes and aquatic life that use the body of water as a habitat as well as the other vegetation in the water that is desirable and vital to the ecosystem before applying chemicals. You should also determine which aquatic herbicide will be best to apply to your pond or other body of water. The size of the body of water is also an important variable which will determine how to best approach treatment of filamentous algae to ensure success while also making sure no fishes and desired plants are harmed.

Step 2: Once you have selected the best herbicide for you to use, you will then need to determine the right dosage and the right timing and temperature to apply the aquatic herbicide to eliminate filamentous algae.  Some algae species can reach troublesome levels in cold water just after ice-out.  However, many aquatic herbicides to tackle algae work best in water warmer than 60 degrees F. When applying herbicides you should also make sure you have safety equipment such as protective eyewear, gloves and long sleeve clothing to protect you from possibly coming in contact with chemicals.

Step 3:
Using a backpack sprayer or hand-pump sprayer, apply the selected herbicide to your pond or lake during ideal temperatures and following the instructions carefully on the product label of the herbicide you chose. If the pond is heavily infested with filamentous algae, it may be necessary to treat the pond or lake in sections and let each section decompose for about two weeks before treating another section. Aeration, particularly at night, for several days after treatment may help control the oxygen depletion. Algae reproduce rapidly, and it is common not to get season-long control with algaecides.  Nearly all products we carry here at Solutions provide at least 3-4 weeks of improvement.  Retreatments are often necessary. There is a more detailed guide on applying aquatic herbicides in our Knowledge base.

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