Common Types Of Pond Algae

The two most common forms of algae that pond owners struggle to control are planktonic algae and filamentous algae.


Planktonic algae (also called green water algae or pea soup algae) are microscopic, free floating algae that give ponds their green color. A normal population of planktonic algae is mandatory for a healthy pond, as they are the base of the food chain and essential for the health of the other aquatic life. When planktonic algae start to bloom and become too prevalent, they will give ponds a pea soup coloration. This usually takes place in summer months or upon the first significant warming trend of the season


Filamentous algae (also called pond scum, pond moss, string algae, hair algae, frog spittle or water net) begins growing on the bottom of ponds on surfaces like rocks and logs and resemble green fur. As the clumps grow, they break loose from the bottom and float to the top, causing ugly green mats on the pond surface. Filamentous algae begin growing in the early spring and are first noticed around the edges of the pond in shallow water. It has little redeemable value to a pond and can even ruin a recreation pond during the summer.