How to Shock Your Pool with Chlorine

Shocking a pool may sound like a significant job, but it's just part of regular pool maintenance. It's a process that involves adding more chlorine than usual (sometimes along with other chemicals) to address an imbalance in the pool.

1. Check and Adjust pH Balance:

   • Ensure the pH balance of the pool water is between 7.2 and 7.6.

   • Use powder or liquid pH adjusters if necessary.

   • Mix the pH adjuster with water in a bucket before adding it to the pool to help it disperse evenly.

2. Prepare Chlorine Solution:

   • Refer to the package instructions for the recommended amount of chlorine needed for shocking, based on your pool’s volume.

   • For a standard guideline, use approximately 120 grams of chlorine granules per 10 m³ of water.

3. Mix Chlorine with Water:

   • Mix the required amount of chlorine granules or liquid with water in a bucket to ensure even distribution when added to the pool.

4. Add Chlorine to Pool:

   • Add the chlorine solution to the pool at the end of the day, after everyone has finished swimming.

5. Check Chlorine Levels:

   • In the morning, check the chlorine level in the pool water to ensure it is at a safe and effective level.

It depends on many different factors. Shocking is part of the preparation when you first prepare your pool for summer use, if you haven't used your pool for a week or so, or if you haven't treated the pool for more than a week. If a pool is used heavily, you may also need to shock it regularly. Pools in sunny areas may require more frequent shocks as well.

Generally speaking, you will need to shock a regularly-used pool every few weeks. But it's essential that you test your chlorine levels to see if it's time to shock. If the pool water has fallen below 1 PPM (parts per million) of chlorine, you will need to shock it to bring it up to standard levels.

How Long After Shocking Pool Can You Swim?

When you shock a pool, the chlorine level will rise to 5-10 PPM. This kills off any microorganisms and cleans the water. However, it’s important not to swim in the water until it tests safely below 4 PPM.

How Do You Know If Your Pool Needs Shocking? 

Chlorine Levels:

• Test the chlorine levels regularly. If they fall below 1 PPM, it's time to shock the pool.

Water Clarity:

• If the water appears cloudy or has a strong chlorine odor, it may indicate the presence of chloramines, signaling the need for shocking.

Algae Growth:

• Visible algae growth on the pool surfaces or in the water requires immediate shocking to prevent further spread.

Heavy Usage:

• After a pool party or heavy use, shocking helps maintain water quality by addressing the increased load of contaminants.

Can You Shock a Pool Too Much?

Yes, you can shock a pool too much. Over-shocking introduces excessive chlorine, which can cause skin and eye irritation, and damage pool liners and equipment. It is crucial to follow the manufacturer's recommendations for the correct amount of shock based on your pool's volume.