photo by dlondon95

Black Beard or Black Brush Algae

This algae form is aptly named as it grows in a group of small threads or tufts that appear to be small areas of brush or like a beard. Don’t let its grey black appearance fool you. It is in the Rhodophyta family and is actually a red algae. Rhodophyta is primarily a marine algae, but some freshwater strains are common as well as the saltwater species.

Prevention is the best plan of attack! Once started it will quickly engulf everything that doesn’t move inside the aquarium. When growing on plants, the Black Beard algae can actually block the light and stop photosynthesis, which in turn can lead to the death of the affected plants. When it first begins to grow Black Beard algae is noticed on the perimeter of the affected leaves and completely covering the stems. If left untreated it will spread across the leaf surface and begin to suffocate the host plant.

When Black Beard algae begins to die it turns into a bright pink/red color. No big surprise as this is a form of red algae after all. If conditions continue and BBA continues to die, it will then turn a shade of light grey before falling off its mooring.

Common Causes

Unstable or too little CO2

This has to be the number one cause! When CO2 is in short supply or when it is unstable, plants are not able to use all the nutrients in the water along with available light for phosynthesis. This type of environment leaves the door wide open and Black Beard algae will jump at the chance! In a moderate to high light tank, stable CO2 supplementation is required or you will forever be dealing with Black Beard algae.

Low pH

It has been noted by many that African Rift or other tanks with higher pH tend to be free of Black Brush algae. Therefore, one theory is that this algae form does not grow well in these types of environments; however, it definitely thrives in lower pH environments.

Improper Fertilization

Overdosing or unbalanced fertilization. Fertilizers, both in the water column and in the substrate, must be balanced with lighting and carbon dioxide supplementation to control algae. A properly balanced tank will have:

• 10-20 PPM Nitrates (NO3)
• 10-20 PPM Potassium (K)
• 0.5-2.0 PPM Phosphate (PO4)
• 10-30 PPM Calcium (Ca)
• 2-5 PPM Magnesium (Mg)
• 0.1-0.5 PPM Iron (Fe)
• 4+ degrees General Hardness (dGH)
• 4+ degrees Carbonate Hardness (dKH)

Removing BBA

Increase or stabilize CO2 levels

Try to maintain 25-30 PPM CO2 in a planted tank. Just like all living things, aquatic plants require carbon to grow. When enough carbon dioxide is trapped in the water column, plants will grow quickly. And, this growth also indicates that plants are taking in nutrients and light. You will notice that Black Brush algae will begin to die with enough CO2 available.

Spot Treat

Can use Seachem Excel, Metricide or Hydrogen Peroxide to spot treat Black Brush Algae. Be careful to use these products sparingly as too much can have a negative impact on fish and inverts as well as on plants known to melt, such as Cryptocorynes or Vallisnerias. Stop the water current (filtration and bubblers) or remove affected plants for treatment. Using a syringe, apply product directly on the Black Beard algae. Wait an hour or two before turning on the filter to restart the current.

Elbow Grease, Toothbrush, Razor, Magnetic Scrapers, etc.

When BBA attaches itself, it is firmly rooted and can be very difficult to separate it from the glass, gravel, hardscape, silicon seams, etc. On the hard surfaces it will take a lot of effort to remove. Spot treat with one of the liquid products above can help to make this job a bit easier.

Proper Tank Maintenance

It is highly recommended to follow a sound weekly tank maintenance plan. Weekly water changes are critical in replenishing the lost minerals and to stabilize the pH-GH-KH system to avoid an overly acidic environment; not to mention keeping the debris cleaned up. Do not overfeed.

Bleach Treatment

1. NEVER pour bleach into an aquarium!!
2. Make a 1:19 parts solution of bleach and water. Works out to a little more than 1 cup household bleach to a gallon of water.  Some plants are sensitive to bleach, so best to test on a single stem or leaf to see how it reacts before dropping all stems or entire plant into the solution.
3. Set up a second bucket filled with water that has been triple dosed with a dechlorinator
4. Remove affected plants and non-pourus hardscape items
5. Do not leave plants in the bleach solution for more than 30 seconds. Non-pourus hardscape items can be left to soak longer if wanted. Immediately transfer into the heavily dechlorinated water. Let soak for an hour or two.
6. Rinse with fresh water until no smell of chlorine remains
7. Again soak in another bucket of heavily dechlorinated water, to be safe
8. Return to aquarium
9. In a few days BBA should be turning red, telling you that the treatment has weakened the algae

Algae Crew

1. Amano Shrimp
2. Siamese Algae Eater (SAE) – These are schooling fish that can become aggressive when not kept in schools. Only use them in a larger aquarium to house the school.  As these fish age they will discover the flakes and/or pellets offered to your other inhabitants.  Once this happens, they will slow down on eating algae.  For this reason SAEs are most efficient when very young.

Things to Avoid

1. Algaecides. The primary ingredient in algaecides is typically copper. It will kill Black Brush algae as well as your plants and invertebrates.  Plus the fact that algaecides do nothing to correct the root cause, so algae will continue to return and drive you insane trying to stay ahead of it.  Find the root cause, take steps to correct it, and algae growth will greatly slow down.
2. Over cleaning.  Aquarium systems may always have some algae in them; but avoid over cleaning or this can impact the Nitrogen Cycle, which may lead to a host of other issues.