Is it Safe to Swim in Green Pool Water?

It’s a terrible surprise to find your pool water green. You may be concerned about whether it’s harmful, if you’ve done something wrong, or even if your envious neighbors have played a joke on you. The most probable reason for your pool’s green hue is an imbalance in the chemicals. There are a few reasons why your swimming pool water might be green in both in-ground and above-ground pools, and the remedy will differ depending on the type of imbalance you have.

pool is green
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Why is my pool green?

If you’ve ever gone swimming in a pool that’s turned green, you know how unappealing it can be. Not only is it off-putting to look at, but it can also be dangerous to swim in – especially if you don’t know what’s causing the discoloration.

There are a few different reasons why pool water can turn green, and understanding these causes can help you take the necessary steps to prevent it from happening again.

Overgrowth Algae

The most common reason for green water in your pool is algae. Algae are generally kept in balance by water circulation, natural die-off in the winter, and appropriate chemical balance. Algae may bloom if the circulation or chemicals are incorrect, resulting in a cloudy and green pool. Lighter green color indicates that it is most likely a brand new formation, whereas a deeper green may signal a more serious issue.

While algae in ponds and streams are natural, an overgrowth of algae in a swimming pool is more concentrated and poses a greater health risk. Furthermore, its presence indicates there’s an imbalance that might also indicate dangerous germs development. Don’t go swimming until the water is free of algae again.

Related Article: How to Get Rid of Algae in a Pool


The second cause of pool water looking green (or yellow) is pollen. Pollen is created by nearby flora and trees, which are carried into the pool water by the wind. Because pollens are too tiny for a traditional pool filter to remove, the quantity of pollen will persistently increase over the year.

As the amount of pollen in the water rises, it settles on the liner and may be mistaken for green or mustard algae. When the pollen level continues to rise, the entire pool’s water can become green eventually. Pollen, on the other hand, is completely safe and has no negative effects on health.

Lack of Chlorine

Water that isn’t chlorinated, especially if it has an algae bloom, is hazardous to swim in and can serve as a breeding ground for mosquitoes and other insects. Chlorine is used to purify water, including the majority of municipal drinking water, because it can destroy almost any microbe that might be hazardous to humans. If the proportions are correct, the chlorine will keep the algae at bay, but if there isn’t enough, the water will gradually become green as the algae take over. 

Browse for The Best Chlorine Tablets for a Clean and Clear Pool

Unfortunately, if you use too much chlorine, the metals in the pool water will oxidize and turn the pool a different color. If you’re having trouble balancing chlorine levels, talk to your local pool expert about other options for sanitizing your pool.

Filter Not Cleaning Effectively

The filter in your pool has a vital function: it sifts out little debris and dirt from the water, removing algae and pollen as the water is pushed through. There are a few reasons it may not be cleaning effectively. In warm weather, a pool filter should be on for eight hours each day, and if many people use it, possibly longer. If you’re already running it for the appropriate length of time, the filter may require cleaning or replacement.

Suggested Article: Everything You Need To Know About Swimming Pool Filter Replacement

Contact a professional pool service provider to ensure clear water.

It’s reasonable to believe that you can keep the chemical balance of a pool on your own. Larger pools are more challenging since more debris enters them and there is additional filtration and cleaning to do. It’s a good idea to hire a pool professional to reset the chemical levels in your pool if you don’t know how to shock a pool to reset the balance, how much chlorine to use, or how to bring down an elevated pH level. A pool specialist may be able to provide you with more specialized care advice if you know how to do those activities but are having recurring pool difficulties.

Visit Briphen Pool Cleaning & Pest Control and get in touch with them if you have any additional questions about how to deal with a green pool or any other water care problem.

Briphen Pool Cleaning & Pest Control is a family-owned company that takes pride in providing the best pool service and care to its customers. Their team of experts will take care of your pool needs, from regular cleaning to complete maintenance services.  Contact them today to schedule a free consultation.

Briphen Pool Cleaning & Pest Control

2750 South Hardy Drive, Suite 1A, Tempe, AZ 85282

(480) 741-2798

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