Swimming pool water is supposed to have a light blue hue to it. So if you start noticing your water turning green, that means something has gone wrong. There are actually several causes of green pool water including algae growth, poor circulation, not enough protective chemicals, and more.

When does pool water turn green?

Pool water turns green when algae is allowed to grow for too long. Algae is constantly trying to grow, but it can be prevented with careful management.

High pH levels, not enough chlorine, and poor filtration and water circulation all contribute to the growth of algae. High pH levels come about when you have foreign substances like cosmetics, oils, and dirt in the water. So it is important to regularly check your pool’s levels or ask your pool management professionals how to take care of your situation.

Low chlorine levels can happen either because a pool owner simply hasn’t been using enough or the chlorine is evaporating too quickly. To solve the evaporation issue, you can make use of a water conditioner called CYA, or cyanic acid.

And if you want to prevent poor circulation, check your filter for debris and blockage and make sure your pump is running when you’re not swimming. In the high summer heat that can reach 100 degrees, your pump may need to run for up to 10 hours a day. The general rule is to run your pump one hour for every 10 degrees of air temperature above zero.

Getting rid of green pool water

The first step in cleaning up a pool is finding out what is wrong. So using a chemical test kit to measure the chlorine and pH of you water is the go-to action. If your chlorine is low, you can use a shock treatment to bring your levels back up. Algaecide can be used as a supplement to this process as well. 

If your pH is out of balance, or not at a neutral 7-7.8 on the pH scale, then you’ll need to bring it back into balance before treating your pool. Ask your pool professional what the best course of action for your pool is because treatments vary for chlorine and saltwater pools, plus size  makes a difference. But the basic rules for pH are to add an acid if the number is too high and add a base if the numbers are too low. Sodium bisulfate will lower a pools pH and sodium carbonate will raise your pH number.

Don’t worry if your pool looks cloudy after you kill your algae. That is just what algae looks like after shocking it. To clean out your swimming area, run your pump and give the walls of your pool a good scrubbing to remove any leftover dead algae.

At Pristine Pools, we value proper pool care. That is why our services include weekly maintenance plans. So if algae does decide to grow in your swimming pool, you can have a professional on standby to step in and take care of it. Many pool owners like to care for their pool on their own as well. And that’s great! Just be sure you are following the right steps before taking action.