black algae

Are you trying to get rid of black algae in your pool and nothing seems to be working? Black algae are very hard to get rid of because its roots get deeply rooted in the side plaster or in concrete pools.

This alga has a lot of layers that protect it from the normal chlorine levels. You need to very relentless when trying to get rid of this algae.

Black algae originally come from the ocean, so if you have forgotten to clean your bathing suit after swimming in an ocean and used the same suit in your pool, there is a high chance that it is the cause. Therefore, you should always remember to clean your bathing suit after swimming in the ocean.

Black algae is a big nuisance in the pool. Here’s how to get rid of it and prevent it from coming back.

How to Spot Black Algae

Not all the dark spots in your pool are black algae. You need to know if what you are dealing with are black algae before begging the process of removing it. Here is how you can tell if the dark spots in your pool are black algae or not.

  • Black algae do not brush off easily from the walls
  • It harbors in the rough areas of the pool plaster
  • The spot is not free floating and it is either blue, green, or black
  • You can easily confuse it with a mineral stain that can discolor the tiles.
  • It is found even in pools with proper sanitation and filtration

Spotting black algae requires you to conduct regular cleaning of your swimming pool. The earlier you deal with these growths, the easier it will be to contain it.

Getting Rid of Black Algae

When trying to get rid of black algae, here is what you will need:

  • Pool shock treatment
  • Chlorine tablets
  • A pool brush and a pole
  • Algaecide
  • Granular chlorine

Be prepared for a ton of brushing, and you can always call a professional pool service if you are not up to the task. Here is a guide on how you can clean your pool.

The first thing you need to do is to test the chemistry of your pool water. You want it to have a normal PH level of 7.4 -7.6 and alkalinity levels between 120 ppm and 150 ppm.

1. Clean and Sanitize Everything

Thoroughly clean and sanitize your tool so that you do not end up adding more algae or introducing any new bacteria in your pool. Spray your tools and scrub them with a chlorine solution.

Clean all your floats and toys with bleach and wash all bathing suits in a machine and dryer. Put your maintenance equipment in the pool too so that they can be sanitized as you clean the pool.

2. Clean Your Filters

Do not forget to clean your filters even when you do not see black algae inside it. Follow the manufactures instruction for cleaning it. The sand and DE filters have to be back-washed and rinsed a number of times.

3. Scrub the Pool

Use a nylon brush to thoroughly brush the sides and the bottom of your pool. You will have to do this till all the algae are brushed away. If your pool is made of concrete or a natural element pool, then you will need a wire brush or a very stiff brush to remove the algae’s protective layer.

You can use a softer brush for a vinyl pool. Once you have scrubbed all the algae away, scrub the pool one more time just to be sure.

4. Scrub the Pool with Chlorine Tablets

Break one chlorine in half and use the rough side to scrape the areas that had been affected again. Do not forget to wear gloves if you did not have a pair on yet. This will help to remove the protective layers of any stubborn algae and will expose the roots, allowing the chlorine to get to them and kill them.

5. Shock Your Pool

A good shock treatment will help to kill all the bacteria and growths in the pool. Get a super shock chlorine treatment for this.

Since this is not your normal routine cleaning, add 3 pounds for every ten thousand gallons of water that your pool holds. This will completely destroy the DNA of the algae.

6. Add Granular Chlorine

This will make sure that your pool is safe for swimming again. Your skin does not have to suffer because of the result of the harsh chlorine treatment.

Follow the manufactures instructions but concentrate on the areas that had the algae. Skip this step if your pool has any dark surfaces because it causes discoloration.

7. Add Algaecide

If you do want to deal with black algae again, you will want to add algaecide too. A bottle should be enough to treat 15,000 gallons of pool water. It will prevent any future outbreaks.

8. Run the Pump

Give the treatment at least 24 hours to settle then run your pump for another 24 hours, then 8-12 hours a day in the next season. If your pool has a dark color, run the pump immediately so that the treatment does not discolor it.

9. Brush the Pool Again

After the first shock treatment, brush your pool 2-4 times a day and concentrate more on the areas that you had spotted them. Remember, the roots dig deep into the walls and they might appear gone, so you do not want to take any chances.

Shock your pool and brush it after 3-4 days with the normal amount of chlorine treatment.

10. Clean the Filter Again

Cleaning the filter after the treatment will help to remove any residue left behind by the algae. Rinse the DE and filter a couple of times just like you did before to remove all the organisms.

11. Check for Algae

Black algae are very stubborn and you might spot some back spots starting to creep back in your pool. Should you see any even if it is after several weeks, shock your pool and brush it again twice a day.

Now that you have successfully been able to get rid of all the stubborn black algae in your pool, you definitely want to relax and enjoy swimming in your pool once again. However, this is not the end of the road.

You can continue with the regular weekly pool maintenance practices from your pool service providers like brushing it down, checking its chemistry levels, vacuuming it, and cleaning the filters weekly. Run your pump daily to get rid of any items in the pool.

How to Prevent Re-Growth

Just because your pool is now clean does not mean that you will not have to deal with black algae ever again. If you did not get it this time, be more aggressive and you will get rid of it.

If your pool is now black algae free, you definitely want to keep it that way. To do this, you will need to:

  • Wash all your swimsuits, toys and floats after you have been swimming in the ocean
  • Maintain the proper chemistry levels of the pool water. Make sure you check it regularly
  • Always run your pump 8 to 12 hours each day throughout each season to filter off any tiny spores
  • Brush and vacuum your pool regularly to keep it clean. Use a quality brush and vacuum
  • Clean and sanitize all the pool equipment toys, floats, ladders, steps, covers, diving board, solar blankets, and any other thing that is in contact with the pool.
  • Shock your pool weekly. 1 pound per 10,000 gallons of pool water. Use an extra heavy chlorine treatment to make your pool a harsh breeding ground for the black algae

Remember, stopping black algae from growing is better and easier than getting rid of it. Be keen with your cleaning procedure, especially if you are doing it yourself, otherwise hire a pool service company to help service and maintain your pool.

Is Black Algae Dangerous?

This is one of the commonly asked questions when it comes to black algae. They can be compared to weeds in the garden, they are a nuisance, a sore sight, but are not dangerous and cannot get you or your children sick.

However, in as much as they are not dangerous, they can encourage the growth of other forms of bacteria that