Why Does My Pool Have A Green Algae Color?

dirty pool in pleasanton ca

September 19, 2020


Ryan Steele

Many pool owners find themselves in a confusing situation. Their pool water has turned green and suddenly they no longer want their family/ friends to dive in. What is the right thing to do? First and foremost, let’s learn the top reasons why pool water turns green in the first place.

Green pool water is an indication of high algae/ bacterial growth. A green pool is seen as unhygienic. However, there are several reasons why this occurs and how to select the right service for help. Maintaining your pool with a reputable service company is the best way to save money longterm.

Poor Filtration

Poor filtration is the main culprit of green pool water. A pool’s filter is responsible for filtering and removing various debris and algae. The 4 types of filters are sand, glass, cartridge and DE. Depending upon which type of filter you have, the filtration’s ability to remove toxins will vary. The biggest threat to proper filtration is clogged or broken filters. For this reason, contacting a knowledgeable professional is essential.

Unbalanced pH

The pH of pool water must be between 7.2 and 7.8. This is considered a normal and “healthy” range. A pH lower than this means chlorine is not working effectively in the pool. This can lead to rapid bacteria and algae growth. If the pool turns too acidic, metals and plastics will become corroded in the water.


When the pool is not properly cleaned, phosphate will buildup. These organic debris will amass and add to phosphorus in the pool. With the inevitable heat of summer, algae grows on the debris.

Pool Service in Pleasanton, California: NorCal

In order to properly treat and care for green pool water, simply contact NorCal Pool Service for hands-on service. Many pool owners do not know what the best strategy is. This is why NorCal provides in-depth service, repairs, cleaning and upgrades to your pool.

A licensed Contractor, Certified Pool Operator, Certified Pool Inspector, Certified Start Up Technician by the National Plaster Counsel, and a life long native of Pleasanton, CA.

Ryan Steele

Owner, NorCal Pool Service

About NorCal Pool Service

We have a pool maintenance package that suites each type of client. From starter packages that just keep the pool chemistry balanced and baskets emptied each week, to Full Service pool maintenance that allows you to kick your feet up and let us do all the work, we have a package right for you!

We also provide pool equipment repairs and installations. We are a Certified Pentair Dealer and Warranty Station which allows us to work with the best brand in the industry. This state of the art equipment is second to none and will leave you with a backyard oasis that will bring you and all your guests a smile.

Years in Business

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