How to Get Rid of Algae in a Pool – Your Guide to an Algae-Free Pool

Pools are often seen turning green or yellowish when they have not been properly treated. This can occur because of lack of maintenance, or if there is a problem with the pool’s overall sanitation and filtration system.

While many people are accustomed to green algae, algae can also be seen with a yellow or black color. Each algae is different and will be caused by slightly different circumstances. Let’s take a look at each algae type and how to get rid of algae in a pool as quickly as possible.

Green Algae

Green algae is by far the most common algae seen in swimming pools. This algae grows because of a filtration problem or lack of proper sanitation. Thankfully, green algae is able to be cleaned with ease and is very easy to eliminate.

Black Algae

Black algae is the most difficult to get rid of. This is the type of algae that is typically seen on the wall of a pool. Black algae will have its roots grow into the plaster of the pool and needs to be removed as soon as possible. With a protective layer that keeps black algae from easily being removed, you will need advanced treatments to eliminate the problem.

Yellow Algae

Yellow algae grows along a pool’s walls and will often be found in shaded areas. This algae is small and may even look like particles of sand. Unfortunately, yellow algae is very difficult to get rid of and will take a pool shocking to get rid of it completely.

How to Get Rid of Algae in a Pool

Algae is naturally occurring in a pool and is removed through regular pool maintenance, shocks and treatments. When you have pool algae, there are a variety of ways to get rid of it.


Pool shocking of varying intensities is the first course of action. This will allow both light and dark green algae to be removed quickly. Depending on your pool’s capacity, you will need various levels of treatment.

  • For every 10,000 gallons of water, one pound of shock treatment is needed
  • Double or triple shock treatments will require two or three pounds of treatment per 10,000 gallons

The following recommendations are given:

  • Light Green Water: A double shock should be performed.
  • Dark Green Water: A triple shock should be performed.
  • Black Green Water: A quadruple shock should be performed.


Flocculants are chemicals that cause the floating algae in the pool to bind together and fall to the pool’s bottom. This can be useful with green or yellow algae that has not covered a large portion of a pool wall. Simply use these chemicals and vacuum out the bottom of the pool afterward. This is a timely process, but it does help greatly when the algae problem is in the beginning stages.

Putting it all Together

Now that we understand how the algae removal process works, we can put it all together to finally see how to get rid of algae in a pool and ensure it doesn’t come back.

  1. Turn on the pool’s filter and pump. Allow these systems to run all day.
  2. Using a pool brush, remove as much algae as possible from the pool’s walls.
  3. Shock the pool according to the recommendations above.
  4. Allow the shock treatment to sit for 12 – 24 hours.
  5. Vacuum the bottom of the pool.

If the water is still discolored or the algae is still present, you will need to continue performing pool brushings and shock treatments until the algae is completely removed.

Once the pool water looks clear and the mold is no longer visible, you will want to utilize flocculants to ensure that all of the remaining algae is removed. These chemicals can be used weekly or bi-weekly to ensure that the pool is algae-free.

Algaecides should also be part of algae prevention. These chemicals can be used every week and will keep algae growth at bay.

Leave a Reply

Your email address will not be published. Required fields are marked *