String algae is not a scientific name of a certain algae species or algae group; it is a common name used for various types of algae that forms strings in the water instead of floating around. String algae is also known as filamentous algae, hair algae, blanket weed and pond scum, while its counterpart (i.e. algae that floats around) is referred to as suspended algae, plankton algae, pea soup, single cell algae and green water. Since there is no exact definitions to rely on, one person can consider tiny strings of algae that grows on a rock string algae, while another person would call it “green slime”, “pea soup but on a rock” or similar. As you can see, the algae field can be really confusing for the pool owner, pond keeper or aquarist in search of reliable information. Misunderstandings are common and it is important to meticulously describe your particular algae problem instead of simply asking “How do I get rid of string algae?”
String algae can grow attached to most type of surfaces, such as rocks, aquarium decorations and pond equipment. String algae can also fill the surface of the water and is then commonly referred to as blanket algae.
String algae will typically enter the pond or aquarium attached to plants. Follow standard cleaning protocol before you allow any new plants into your aquarium or pond. Also keep in mind that string algae can be attached to aquatic vertebrates or float around in the water bag when you purchase new fish.
String algae is fairly easy to remove manually, but you have to be persistent. Using an algaecide might be a good idea for swimming pools, but ponds and aquariums should not be poisoned since it will only wreck havoc with the sensitive eco system and can lead to even worse algae blooms. It is possible to purchase special treatments that will only affect certain types of algae. Don’t use such remedies unless you know for sure that you will have time to manually remove all the dead algae, because if you leave the killed algae in the pond or the aquarium the water quality will drop like a stone and the inhabitants will suffer and possibly die.
Another popular method is to use barley. Barley emits a certain type of enzymes that suppresses the growth of string algae. You can for instance use barley bales or barley extract. Since it only suppresses the growth of string algae, barley will never remove existing algae from the pond or aquarium. Don’t loose heart if it takes some time for the barley to start showing results; it can take several weeks before the enzymes have been thoroughly distributed to the entire pond or aquarium. You can increase the speed by placing barley in parts of the pond or aquarium where the current is strong.
Just like any other algae, string algae need water, light and nutrients to survive. You can therefore combat string algae by following general anti-algae recommendations, e.g. avoiding over-feeding and keeping the levels of organic waste products low. Live plants are good since they will compete for nutrients with the algae.
Central American Cichlids
Frogs and Turtles
Lake Victoria Cichlids
Marine Aquarium Fish
Responsible Fish Keeping
South American Cichlids
Tropical Fish Food