• Rockingham Pool & Spa Solutions

Shock Pool Treatment


We all enjoy the great pleasure of swimming in crystal clear pool water! To be able to do this you need to regularly maintain and shock your swimming pool. Shocking a pool is a great way to bring things back.


When you shock a pool, it breaks up combined chlorine (chlorine + contaminants), plus removes excess bather waste and bacteria after pool use, contamination events, or for the removal of visible algae in the water. Bromine treated pools and spas also use pool shock to reactivate bromide ions in the water.


Shock pool treatment, is the process of adding chemicals to your pool water to;

  • Break apart chloramines (known as combined chlorine)

  • Quickly raise your chlorine level

  • Kill algae, bacteria & other harmful pathogens

  • Helps keep your pool smelling … well, hopefully like nothing at all.


Understanding Chlorine - When testing your pool’s chlorine level, it is important to first understand how chlorine is classified.

Free Chlorine - The desirable chlorine available to sanitize or disinfect the water.

Combined Chlorine - Bad-smelling, undesirable chloramines that form when not enough free chlorine is present to overcome the chlorine demand.

Total Chlorine - The total amount which includes both free and combined chlorine.

How Often to Shock Your Pool? - You don’t want to wait for a bad smell or itchy eyes to happen before you shock your pool. We recommend shocking your pool once a week, or at least once every other week to properly maintain your water chemistry and excellent pool health. The more often you use the pool, the more often you should reach for the swimming pool shock.


In addition to your weekly or semi-weekly treatments, you may want to perform an extra pool shock under certain circumstances, such as after:

  • Heavy pool use

  • After a pool party

  • Rainstorm or winds (especially if your pool collected debris)

  • Major water level change

  • Seasonal start-up & close-down

Think of extra shocks as insurance against wayward algae and other contaminants. There is a lot of harmless matter that gets into a pool and gets in the way of water balance and sanitation. It’s better to take out any bacteria before it has a chance to affect the quality of your water or make anyone sick.


There are 3 main reasons to shock a pool or spa, raising the Free Chlorine level high enough to oxidize or destroy the offending contaminants. These can be called the A-B-C’s of Pool Shock.

Algae: Green, yellow, pink or black, the best algaecide is chlorine, and lots of it. Pool algae growth can be controlled with algaecide, but to kill algae and clear the pool, we use pool shock.

Bacteria & Bather Waste: Bacteria can enter the pool from many sources, most of it harmless variety, however pathogenic bacteria may also exist.

Chloramines, Contaminants, Cloudy Water: Combined chlorine molecules are responsible for ‘red-eye’ and a strong chlorine smell.


To get the best results from shocking your pool you should do the following steps;

  1. Skim the pool to remove leaves and debris

  2. Vacuum then remove pool cleaner

  3. Brush walls, floor & coves

  4. Add shock directly to the pool

  5. Add shock when the Sun is down, this gives your pool plenty of time during the night to free the chlorine and clean the water.

  6. Run your pump for about 6 hours (depending on your pool)

  7. Brush pool to help distribute and circulate the shock

Note: If you shock your pool during the day, the sun’s UV rays will dissolve the chlorine.


Once your pool has been shocked, you are ready to go. Your pool water will be clean, clear, and safe for your family.