Pool Shocking 101
"Shocking” your pool is a vital component of maintaining a healthy swimming environment. The term, "Shocking” refers to the process of adding chlorine or non-chlorine chemicals to your pool in order to raise the "free chlorine” level to a point where contaminates such as algae, combined chlorine (also known as chloramines) and bacteria are destroyed.
When do I need to Shock my pool?
On average it is recommended that a pool owner shock their pool at least once a week during peak swimming season. However, it should be noted that the need to shock your pool should really be dictated by how often and how many bathers use your pool in direct correlation to weather conditions such as long periods of sun or rain.
As a general guide, you should shock your pool when:
- Algae begins to grow in your pool
- The free chlorine level of your pool measures zero
- The combined chlorine level rises above 0.5
How do I shock my pool?
The goal of shocking your pool is to raise the free chlorine level of your pool water to roughly 10 times the combined chlorine level of your pool water. By reaching this mark which is commonly referred to as "break point chlorination,” free chlorine is able to eliminate contaminates and protect the health of your pool.
While achieving break point chlorination varies from pool to pool, the following steps will help you accomplish the shocking process:
- Use an FAS-DPD test kit to identify the free chlorine level of your pool
- Add enough chlorine to bring the Free Chlorine count to reach the Break Point Chlorination Level
- Repeat steps 1 & 2 until Break Point Chlorination level is reached or until:
- The combined chlorine level of your pool drops under 0.5
- An overnight Free Chlorine test shows of 1.0 ppm or less
- Visible algae disappears and/or water becomes crystal clear
Please Note: Establishing the break point chlorination level takes time. If you have any questions or concerns about how to properly shock you pool, we suggest you contact our Aqua Experts for assistance.