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This is how you get rid of black beard algae in your fish tank

The bane of many an aquarist, black beard algae (BBA) haunts fish owners. If you’ve never experienced this easily spreading nuisance, allow us to warn you that prevention will far and away be your best option. Once BBA takes hold in your tank, you may have to resort to drastic actions, including removing live plants and disposing of them. Read up on black beard algae, and stay conscientious about keeping the algae out of your fish tank to begin with. If worse comes to worst, and you do need to remove this water weed from your fish home, follow these steps to get rid of it as quickly and harmlessly as possible. 

Black beard algae grows on wood in aquarium

What is beard algae?

In short, a menace. This is an algae that grows on plants, rocks, and wood. It’s called “beard” because you’ll find tufts of it covering a plant leaf or the tip of a rock. All it takes is one little tendril to wind up in your tank, and it’ll quickly take over. Although “black” is included in the name, you’ll often see a greener color, and BBA actually belongs to the red algae family.

Why is my fish tank getting black beard algae?

Here’s the good news: algae doesn’t spontaneously generate, and it’s not living in the air opportunistically like bacteria, so you can take concrete steps to keep it out of your aquarium. As long as you thoroughly clean new accessories like rocks, wood, and gravel before adding them to your tank, BBA shouldn’t be able to hitch a ride on those items. One of the most common ways that BBA enters the ecosystem is when you add a new animal to the tank. There’s an easy way to prevent this: quarantine. That’s right! Keep your new fish on their own for a bit. In case BBA might be floating in the water with the fish, scoop them out with a net before depositing them in the tank.

Is black beard algae harmful?

Unfortunately, it can be. When black beard algae grows on a leaf, it’s blocking the light that the plant needs to nourish itself. That effectively starves, and can even kill, the beautiful fauna in your tank. So don’t wait until the algae has grown into a small forest to take action. Too much BBA will also throw off the delicate balance of your aquarium. It’s essential to carefully maintain all proper chemical levels in the ecosystem, and you don’t want the algae to interfere with that. 

Black beard algae grows on plants in aquarium

Do fish eat black beard algae?

Yes, a few fish will become your partners in crime to keep the evil algae at bay. Both the Florida Flag Fish and the Siamese Algae Eater (Crossocheilus siamensis) will happily munch down on this interloper. Carefully select these fish from a local breeder since you might find other species that are called Siamese Algae Eater. Introducing the Florida Flag Fish or Siamese Algae Eater will go a long way toward maintaining the health of your aquarium, provided they get along with your other fish and fit into the environment.

How do I get rid of black beard algae?

Prevention and natural algae eaters are the two best ways to eliminate a black beard problem. They both ensure that BBA never gets out of control. However, you need a plan in place in case BBA does take root. 

Check your levels

You typically spend time ensuring there’s enough oxygen in your tank, but be aware that black beard algae thrives in low CO2 environments. If you spot the offending green, you should begin meticulously checking CO2 levels. Adding a CO2 booster is an easy way to help keep the unwanted algae at bay.

Treat with bleach

Once BBA has taken hold, you will need to remove everything in the areas where you see it thriving. That means pulling plants and wood for treatment. You might get away with just clipping some leaves if you catch BBA in the early stages. Otherwise, place everything into a 10% bleach solution for three minutes to kill the algae while keeping the plant alive.

Clean thoroughly

Be prepared to do some scrubbing, bleaching, and conditioning. Regular water changes and careful monitoring are always the best ways to keep your tank healthy. When BBA is present, you will need to take that up a notch, or more. Don’t be surprised if a few tries are needed to truly knock it out. 

When it comes to tank contaminators, remember that an ounce of prevention is worth a pound of cure. Simple measures like checking CO2 levels and ensuring proper lighting all can contribute to avoiding contamination and keeping fish healthy. While we want you to be prepared to tackle BBA if it ever pops up, keep in mind that it won’t instantly kill your fish. Take a deep breath and follow the steps provided here to rid your aquarium of the pest safely and effectively.

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