How to Clean a Green Pool in 24 Hours

Is your pool looking green and uninviting? Don’t worry, you don’t need to drain it and start over. With the right steps, you can quickly eliminate the algae and bring back that sparkling clean water. Here’s a simple guide to help you clear up your pool in no time.

Why Is My Pool Green?

A green pool is usually caused by algae. If the water is light green, it means algae has just started growing. But if the water is dark green, there’s a bigger algae problem. Algae often appear when your chlorine levels or other pool sanitizers are too low.

How to Clear a Green Pool Fast

Follow these 5 steps to get rid of the algae and have your pool looking clear again in just a few days. Stick to these steps to make the process as quick and easy as possible.

1. Scrub the Pool Surfaces Start by using a pool brush attached to a pole to scrub the pool’s walls, bottom, and steps. This helps break up the algae so it can float in the water, where the chlorine can kill it. If your pool has concrete, use an algae brush for the best results, as it’s more effective than a soft brush.
   
2. Check Your Pool’s pH and Alkalinity Use test strips or a liquid kit to measure your pool’s pH and alkalinity. You want the pH to be between 7.4 and 7.6 and alkalinity between 100 and 150 ppm. If they’re too high or low, adjust them before moving on. Proper pH and alkalinity help the chlorine work better to kill algae.
3. Shock the Pool with Chlorine This is the most important step to eliminate the algae. Use a chlorine shock with at least 70% chlorine (calcium hypochlorite) to kill the algae. Even if you usually use non-chlorine shock, you’ll need chlorine shock for algae. Make sure to shock the pool at night, as the sun can reduce the effectiveness of the chlorine.  
4. Run the Filter for 8 Hours or More After shocking your pool, run the filter for at least 8 hours overnight. Ideally, run it 24/7 until your pool clears up. This helps the filter catch the algae and clean up the water faster. Don’t forget to backwash the filter if needed. If the pool is still green the next morning, shock it again with the same amount of chlorine.
5. Test the Water and Balance Chemicals When the water is no longer green and has turned cloudy or clear, test the water again. Check the pH, alkalinity, calcium hardness, and chlorine levels. Add any chemicals needed to balance the water and make sure everything is just right. 
   

Once the water turns cloudy blue, it means you’ve killed the algae. You can use a clarifier to speed things up, but make sure to run the filter for at least 24 hours to remove the dead algae.

How to Prevent Algae from Coming Back

Once your pool is clear again, you’ll want to keep it that way. The most important thing is to maintain proper sanitizer levels. Test your water regularly (at least once a week) and add sanitizer when needed.

If you like, you can also add algaecide as part of your regular pool maintenance. But keeping your chlorine levels balanced is your best defense against algae.

Should I Worry About Phosphates?

Some people say you need to remove phosphates from the water to stop algae. But don’t worry about it. Phosphates are everywhere, and trying to remove them is nearly impossible. Instead, focus on sanitizing the pool and keeping the chlorine levels right.

Frequently Asked Questions About Fixing a Green Pool

How Long Does It Take to Clear a Green Pool?

If you follow these steps, you can usually clear your pool in under 5 days. Adjust your pH and alkalinity, shock the pool at night, and run the filter constantly to get the algae out quickly.

Will Chlorine Clear a Green Pool?

Yes! Chlorine is the best way to kill algae. Use a strong shock with calcium hypochlorite to eliminate the algae. Liquid chlorine works just as well as powdered shock but is heavier to carry and pour.

Can Baking Soda Clear a Green Pool?

No. Baking soda only adjusts your pool’s pH and alkalinity, not the algae. You still need chlorine to kill the algae.

Can You Over Shock a Green Pool?

No, you can’t over shock a pool. The more chlorine you use, the better your chances of killing all the algae. Just make sure to follow the recommended dosage and increase it if necessary.

Will a Clarifier Clear a Green Pool?

No. Clarifiers help bind particles together, but they won’t remove algae. You need chlorine to kill the algae first. You can also use pool floc to sink the algae to the bottom and then vacuum it out, but that takes extra work.

With these tips, you’ll have your pool back to its clean, clear self in no time. Enjoy the water!