How to Clean a Green Swimming Pool

green pool

Wondering how to clean a green swimming pool? If a swimming pool was neglected all winter long, you will have your work cut out for you. Learn some methods to bring your pool back up to speed in time for summer pool parties and barbecues.

How to Clean a Green Swimming Pool

Green swimming pools are far from friendly. Even if you invested in an automatic pool cleaner, chances are you're struggling to see cleanliness. The highest quality pool cleaning bots cannot overcome winter storms and hot, muggy summers. Fortunately, you can bring the blue back to your pool in three simple steps.

Step One

Use a large pool net to remove any debris from the surface of the water. After the top of the pool has been cleared, dunk the net into the water and run it along the bottom and sides to capture any debris under the surface. Take a large pool brush to the sides and bottom, brushing backward and forward. This will eliminate algae growth, which is responsible for much of the green color you see both above and beneath the surface.

Step Two

Run your pool pump for approximately one hour. You will then have to repeat the debris removal process and add in some vacuuming time. This is where an automatic cleaning robot comes in handy if you own one. It will take a bit longer than a traditional brush, but will save you a lot of physical effort. It is also helpful if you are not exactly sure how to clean a green swimming pool. It will do a lot of the tricky work for you.

Step Three

After this initial cleaning is complete, you will have to "shock" the pool. Do this by using two times the amount of pool chemical that you normally would. This will counteract any remaining algae growth, and prep your pool properly for that first season swim.

You must continue to shock at least once a week during the summer, and even more frequently if you are able to. Pour most of the chemicals in the deep end, but don't neglect the pool edges as there is growth there as well. Brush the edges and any other reachable surface so it does not cling and cause damage.

Backwash and Test

Check to see if you need to backwash the pool. If you still see film or cloudiness, you will need to add clarifier to eliminate it. Give the clarifier about four hours to do its job, and then backwash again to flush the filter out one more time. If shock did not clean up all of the algae, then you can brush it one more time and add algaecide. You will then need to run your pump for a good half day or so. Again, if you have a cleaning robot, this will come in handy and help you conserve some energy in warm weather.

Don't forget to check your water level. If you need to add water, do so before checking the PH and chlorine levels. You can then test the water, either on your own or by taking it to a local pool store. It's important you test the water before swimming, so you can remain healthy and ready to swim all season long.


Not knowing how to clean a green swimming pool does not need to ruin your warm weather plans. Many have successfully cleaned such pools without any experience after moving into a new home or bringing new life to a neglected outdoor luxury. Devoting a single weekend can get your pool back into great shape, and with the above instructions, it has the potential to be a simple process that is far from intimidating.

How to Clean a Green Swimming Pool