How to Get Rid of Blue-Green Algae in Aquariums
Are you experiencing mysterious blue-green slime in your aquarium? Or is there a strange smell coming from your fish tank and you can’t find the source? An outbreak of blue-green alga might be the problem. In this article, we discuss the causes of blue-green algae and how to get rid of it once and for all.
What is Blue-Green Algaee?
Blue-green algae (BGA), isn’t actually an algae, but a cyanobacteria. This is a diverse and resilient strain of bacteria that uses photosynthesis to grow plants. In freshwater aquariums, it’s known for its vivid blue-green color, but it can also appear in shades of brown, black, or even red. You might see it as a tiny bit of green algae. It eventually grows into thick slime, covering your gravel and decorations. 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.
Blue-green algae can also be identified by its distinctive 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?
There have been many studies to determine what causes cyanobacteria blossoms. They can have devastating effects on the environment. There are not yet any definitive answers, but they often 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). Improve the water flow by using a stronger filter, adding a powerhead, or moving decorations and equipment around in the tank.
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. Additionally, blue-green alga often returns in a matter of weeks.
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.
You can begin treatment by scraping off as much blue-green alga as possible. 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. It is easier to eliminate an outbreak if you act quickly. To completely eradicate the colony, it may be necessary to repeat the treatment if the blue-green alga is extremely thick or widespread.
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. If you’re struggling with another type of algae, check out our full guide on how to fight the top 6 types of algae in freshwater aquariums:
