How to Get Rid of Blue-Green Algae in Aquariums
Is your aquarium being overrun by a blue-green slime? Or is there a strange smell coming from your fish tank and you can’t find the source? Blue-green algae might be a problem. We will discuss the causes and how to eliminate blue-green alga.
What is Blue-Green Algaeee?
Blue-green alga (BGA) does not exist as an actual algae. It is actually a cyanobacteria, a group of bacteria that uses photosynthetics like plants. Although it is best known for its vibrant blue-green color in freshwater aquariums it can also be found as a black, brown, or red. It may appear as a small spot of green algae, but it eventually becomes a thick slime that covers your gravel, decorations, plants, and other items. While cyanobacteria in aquariums does not usually harm fish, it can potentially kill your plants if their leaves are covered and can no longer photosynthesize light.
Another way to identify blue-green algae is by its distinct odor. It can smell foul, musty or swampy. Once you have learned to recognize the scent, it’s possible to detect cyanobacteria up to two weeks before it’s even visible in the fish tank.
Blue-green algae can be described as a type or photosynthetic bacteria.
What Causes Cyanobacteria in Aquariums?
Since cyanobacteria can have a devastating impact on the environment, many studies have been conducted to identify their causes. While there are no definitive answers yet, they commonly occur in warm, slow-moving, and nutrient-rich bodies of water. In the aquarium hobby, we have frequently seen blue-green algae pop up wherever organic waste has a chance to stagnate in certain areas of a fish tank. If:
– The current in the fish tank is too slow – Hardscape is blocking off a corner of the aquarium that also gets exposed to constant light – The substrate is collecting debris because the gravel hasn’t been vacuumed in a while and there are no animals to churn it
How Do I Get Rid of Blue-Green Algae Naturally?
These possible causes are the basis for the first step: manually remove as much slime as you can using a siphon or toothbrush. Blue-green algae is not something animals like so your clean-up crew won’t be much help. Remove any excess nutrients by doing water changes more frequently, cleaning the filter regularly, and reducing the amount of fish or food going into the aquarium (if overfeeding is a problem). You can improve the water flow by adding a powerhead or a stronger filter.
Photosynthesis is used by Cyanobacteria to produce energy. To starve the colony, some recommend turning off aquarium lighting for three to seven consecutive days. However, this method can end up harming your plants (which also use photosynthesis) or causing spats among the fish. The blue-green algae can also return within a few days.
Cyanobacteria: Can Medicine Treat It?
This stubborn bacteria is a problem for many people. However, it is extremely resistant to an antibiotic called erythromycin. This medicine is safe for fish, plants, and invertebrates, and it will not harm the beneficial bacteria in your aquarium. Fritz Slime Out is our favorite, as it’s formulated to reduce cyanobacteria and not increase phosphate levels.
To begin treatment, scrub off as much of the blue-green algae as possible and remove it with a siphon. After cleaning the substrate, fill the tank with Slime Out (1 packet per 25gallons). Let the aquarium rest for 48 hours before performing a 25% water change. Add an air stone or other filtration that agitates the water surface to help ensure the fish have enough oxygen during the treatment. The earlier you treat the outbreak, the easier it is to eradicate. If the blue-green algae is very thick and widespread, you may need to repeat the treatment several times to completely remove the colony.
If you address the underlying causes of cyanobacteria and treat it with Slime Out, you should have no problems getting rid of it in your fish tank. Our complete guide on how to eliminate the top 6 types in freshwater aquariums is available here.