What Causes Green Pool Water?

We all love diving into a sparkling blue pool in the summer to cool off, but nothing ruins that fantasy quite like green pool water. Maintaining the colour and cleanliness of our pool can seem like a daunting task – but with the right knowledge and products, it can be quite simple. Here are some of the most common reasons for discoloured pool water, and how you can prevent or treat it.

Green pool water is not something anyone enjoys, but it is an issue that plagues many a pool owner. Even with the best of intentions before putting your pool to bed for the winter, algae can still take root and before you know it, your entire pool is covered in it.

Green algae water

What causes green pool water?

The green colour you see in discoloured pool water is caused by algae that takes hold when pool chemicals are not kept in the proper balance. Algae is relatively easy to kill with the proper chemicals and Ph levels, but for some unlucky homeowners, it can be a real ongoing problem. There are many things that can happen to cause your pool’s water to turn. The most common is a lowered Ph level, which can be the result of excessive rain, having too many people in the pool at once, or allowing pets to have a dip. Failing to properly maintain your pool’s chemical ratios can also throw the Ph balance off.

Man cleaning pool with skimmer

How do you prevent your pool water turning green?

Preventing a green pool doesn’t have to be complicated, but it does require a certain level of diligence. The pool’s chlorine levels, Ph, and other chemicals should be checked and altered frequently to keep the atmosphere one where algae will not easily take root and grow. This is especially important when circumstances come into play that are beyond your control, just as excessive rain. When it has been raining frequently, it becomes all the more important to check and recheck your pool’s levels. Additionally, leaving your pool to sit all winter also provides ample time for algae to bloom. Continuing some level of maintenance, even during the seasons when you can’t swim, can help prevent your pool from turning green. If you don’t have the time to do these tasks, or you feel that it’s too daunting, hiring a pool specialist might be the way to go.

two kids swimming in blue pool water

What do you do if your pool water turns green?

First of all, it should go without saying that you shouldn’t swim in green pool water. It could cause illness in some individuals.

If your pool is already green, then you have a few options. You can try to alter the chemicals yourself until the water is clear again, or you can hire a professional. If you attempt to treat the pool yourself, it’s important that you perform the procedures properly to avoid throwing things off even further.

Pool chemicals can be tricky, and it’s easy to alter things too much in one direction or another and wind up with even more problems. In many cases, hiring a professional pool cleaner or maintenance crew is the fastest and easiest way to help a green pool. They will already know exactly what to use and in what amount to clear the water up again in no time. They can also come out and help you keep the pool clean all summer long.

Blue pool water with light reflecting

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      Brit McDowell

      Lifestyle Specialist & Subject Matter Expert

      Brit McDowell is a Product Specialist at Localsearch with a background in marketing, business and tourism management. Aside from her specialisation in technical processes, Brit is known for her green thumb and growing succulent collection, love of dogs (especially Dalmatians), eye for home interior and fervour for travel. Brit is also a Lifestyle Specialist on the Localsearch Blog and enjoys sharing her research and knowledge in home and gardening services, food, beauty and general lifestyle tips and tricks.