Are chlorine and shock the same thing?

SKIMMER NOTES: No. Chlorine and shock are not the same thing. Shock has a more intense chemical strength than the traditional chlorine sanitizers, and it also differs in how you should apply it to your swimming pool.

Are chlorine and shock the same thing?

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  • Category:
  • Pool
  • Pool Maintenance

Short answer: No. Chlorine sanitizers and shock are similar but different in strength.

What IS the difference between chlorine and shock?

Granular chlorine, liquid chlorine, chlorine tablets and granular shock all have similar active chemicals that sanitize your pool. What’s different about shock is the strength of the chemical and how you're supposed to use it.

How much chlorine do you need to shock a pool?

Unfortunately, you can't shock your pool using your regular 3-inch chlorine tablets. Common chlorine sanitizing products are great for maintaining chlorine levels, but not necessarily eliminating new waste, bacteria and algae.

A good shock product should raise the free chlorine above 5 parts per million for several hours to destroy bacteria and chloramines. Keep in mind, if you have visible algae of any kind (black algae, mustard algae or green algae), you may need to double or triple the normal dosing of pool shock to eradicate the problem. That’s where the power of shock come in. For example, some 1-pound bags of shock treatment can deliver 7 parts per million of free chlorine per 10,000 gallons of pool water.

As always, we’re here to help. If you have questions, contact our help line at 1-866-HTH-POOL or talk to our experts with our live chat!


Please read the following important reminders before adding pool chemicals to water:

• NEVER mix products together or dissolve before use.

• ONLY enter pool when FAC levels are below 4 ppm to prevent risk of bodily harm.