Hello! I’d like to share some information about a type of algae known as blue green algae. We recently had a small amount of this type of algae in one of our tanks. Here are the steps we took to combat and get rid of this algae.
Blue green algae, the common name for cyanobacteria, grows quickly and can cover the surfaces in an aquarium if left alone. Like true algae, make up a portion of the phytoplankton in many water bodies. However, when disturbed it comes off in sheets of slime. Physically removing this type of algae is possible, but unlike some other types of algae, blue green algaea will remain visible in the water column when scrubbed off of a surface. Small amounts of blue green algae is manageable and harmless, however, larger amounts may require more work and immediate attention. A severe overgrowth of Cyanobacteria can cover every surface in the aquarium and gather into a foamy scum at the surface of the water as well as releasing toxins that could harm livestock. Blue green algae is typically blue-green in color, but it can be greenish-brown to black, or even red in color.
It is also important to know that algae eaters do not eat this type of algae.
There are several possible causes for blue green algae in an aquarium. It can come from other aquariums by sharing plants or other materials infected with the algae, excess light, high waste levels, low oxygen levels, and/or low water circulation. The cause of the algae outbreak in our aquarium could be excess light and low oxygen levels. We have very strong lights to help our aquatic plants grow optimally. In addition to strong lights, the temperature of our aquarium is in the 85-90 degrees Fahrenheit range. We adjust our temperatures warmer than the average aquarium to help lower the chances of sickness and disease for our livestock. However, warmer temperatures in water lowers oxygen levels. With high levels of light and low levels of oxygen, blue green algae grew in our aquarium.
In our tank, we had a small amount of blue green algae on our soil substrate as well as some leaves on a few plants. The algae was very manageable and completely harmless, but we acted quickly to prevent further spread of the algae. To combat this algae took did a few things:
- 5 to 10% water change until algae is gone
- 200 mg erythromycin phosphate/10 gallons water
Erythromycin is an antibiotic that is commonly used to get rid of blue green algae in aquariums. We diluted the erythromycin with a cup of tank water, switched off the filters and took a turkey baster to apply the erythromycin solution to the algae infected areas. By switching off the filter, the infected areas can be easily treated with the antibiotic. Within two days, the algae was gone.
In more severe cases, physical removal and a larger water change may be necessary. In my opinion, Blue green algae is actually one of the easier types of algae to remove… if you remove it early. Don’t wait until the algae is out of control to respond!
Thanks for reading!