Scary Black Spots in the Swimming Pool: Black Algae


black algaetrineHow to avoid the awful black spot this summer

It’s first warm day of spring. You go outside, bursting with excitement, and are imagining your first plunge in your refreshing, clear blue pool water. Then all of a sudden, as you look into your previously beautiful pool, you find it is covered in nasty looking black spots. This is known as a ‘black spot’ algae infestation and is a particularly difficult type of algae to get rid of.

Black spot algae tends to cling to the walls and floor of your pool. It is similar to the black algae that is sometimes found growing on your bathroom shower tiles or ceilings. Here are some preventative tips to help you avoid the dreaded black spot this summer, as well as some treatment options if you have already noticed black spot algae in your pool.

What is ‘Black Spot’ Algae?

Black spot algae is the most difficult type of algae to cleanse your pool from. It is named ‘black spot’ because of the dark looking spot on top of the growth that is visible on the sides or the floor of your pool. The top part of this algae is usually the only visual part; however, if you only remove the dark spot, the algae will grow back within a couple of days. This algae grows in layers and the head protects the layers underneath from destruction.

Tips to Prevent it

When it comes to this particular kind of algae, prevention is much easier than cure. The black spots are especially difficult to remove once they have attached themselves to the walls of your pool.

What are the best ways to help prevent this algae growth? The first tip is to keep your pool’s free chlorine levels above 1.5 parts per million. After putting chlorine in your pool be sure to see that the chlorine is evenly distributed by allowing the water to circulate properly. This is important to do because it lets the chlorine reach the tight spaces the black spot algae would be most likely to grow, such as tight corners and deep ends of your pool. Make sure to regularly vacuum and remove leaves in your pool as well.

Tips for Treatment

Ask someone at your local pool store or carefully follow all of the directions listed on your black spot algae treatment to make sure the roots of the algae are destroyed and not just the head. In particularly difficult situations, numerous treatments may be necessary.

Check out these products to help rid your pool of black spot algae:

  • Black Algaetrine