How to Clean a Green Swimming Pool (Algae)

This guide covers the ways to take on a green swimming pool. Turning your pool from green back to crystal clear will take some time. With a little patience and work your green swimming pool will be ready to swim in again.

1. Run the pump and filter for 24 hours - Running your filter will help filter out tiny particles that are also to blame for your green swimming pool. Due to the fact that your pool will be running 24 hour, your filter will become clogged quickly. You will need to backwash your sand or d.e. filter whenever the pressure increases 8-10 psi above the normal reading. For example, if my pool normally reads 12 psi (when it's clean), I would backwash when the gauge reaches 20-22 psi.

2. Remove any large debris and leaves - Using an aluminum leaf rake or leaf bagger attached to a telescopic pole, remove the larger debris found on the bottom of your swimming pool. The large debris needs to be taken out first to ensure that you will not clog your pool cleaner, skimmer, main drain, filter, or piping.

3. Balance your chemical levels- A balanced water chemistry is essential if you want to get the pool clear.

4. Brush down the surface of the pool- Have you ever touched algae? Algae usually has a slimy coat. That slimy coat protects it. Brushing helps remove that protective coat and expose it to the chemicals in the water. Brushing down the walls will help remove some of the algae that is growing on its surface. Any algae that remains will be killed when the pool is shocked. 

5. Shock the swimming pool - Using pool shock will kill off bacteria and algae that is still in your green swimming pool. Most likely if your pool is a deep green you will need to add several bags of pool shock over a period of days. This step should start to clear up your swimming pool.

6. Algaecide - An algaecide will help treat and prevent the return of algae. An algaecide should be part of the weekly maintenance. This step is optional, but highly recommended.

7. Remove any remaining debris - Using a leaf rake, leaf skimmer or an automatic pool cleaner, remove any remaining debris left in your swimming pool. The clarity in your swimming pool should have improved drastically by now. If not, repeat steps 5 and 6.

8. Your swimming pool should be crystal clear once again. A little weekly maintenance (water testing, adjusting chemicals) will help prevent the swimming pool from turning green again in the future.

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