Do You Know Why The Pool Water Is Green?

Posted by Tim Roadnight
Why is the Pool Water Green?

Cleaning and maintaining a swimming pool can be a big job and a big responsibility. If the maintenance is not kept up with, then you are risking unhealthy swimming conditions as well as an eyesore in the backyard. You have recently gone to check the pool, and you see that the water has a very sickening green color and you wonder, why is my pool water green?

What Causes Green Pool Water?

There are several reasons you can have green pool water including a lack of chlorine, the presence of pollen, and the presence of oxidized metals. Even if you feel that you have kept up with the maintenance and you clean and skim the pool regularly, you may still see the green water.

Lack of Chlorine

If your pool is lacking chlorine, then it is not safe to swim in. It becomes a breeding ground for algae, mosquitoes, and other insects. Algae will feel slimy if you touch it and will typically begin to form on the pool walls and the bottom of the pool. The only good way to remove the algae is by scrubbing it off.

It is important to regularly check the chemical levels in the pool, and if you see algae, then you should use an algaecide and super chlorination to rectify the problem.


Pollen will sit on the bottom of the pool and can even be mistaken for algae. Pollen is fine and usually, cannot be caught with sand filters so skimmer socks should be placed over the skimmer basket to help remove pollen. It is important to clean this out periodically during the process. You can also add a flocculant to help clear out the remaining pollen until you see a clear and sparkling pool again.


If your pool water has turned green due to metals, then the color will be a consistent green color, and not as dark as when algae is present. It will still remain relatively clear; it will just have a green hue. If it is metal causing the color, then you will likely notice it once the pool has been shocked.

To treat green water due to metal, simply add a sequestrant to the water so that the metal particles will come together and the filter can begin to clean them out of the water. Once finished, chemically clean the filter to remove any residue.

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