How to shock a pool is something that every pool owner must know how to do. It’s an essential process to keep the water clean and ensure that the pool is safe and clear to swim in every time. For regular maintenance, you must shock your pool ideally once a week–but you can also do it at least once a month. If your pool is getting a lot of action or is just susceptible to algae build-up, you’ll need to shock it even more often.
Why Shock a Pool?
Many first-time pool owners often wonder what pool shock really is. Shocking a pool is another term for super-chlorination or the process of adding chlorine to a pool to sanitize it. Here are some reasons why you must do it:
Keep Chlorine Levels Right
Chlorine is the top pool sanitizer. Once you put it into your pool, it actively cleans the water. At this point, it’s known as ‘free chlorine’ (FC). After some time or multiple uses, the used chlorine becomes less effective because it has been mixed with other chemicals, such as sweat, sunscreen, makeup, etc.
This compromised chlorine is now known as ‘combined chlorine’ (CC) or chloramines. Pool shocking is primarily done to increase FC and reduce CC. The way to know how much shock to add to a pool will depend on these levels, as well as the volume of your pool.
Sanitize Pool Water
When there’s enough chlorine in the water, the pool will be well-sanitized. That means that it will be safe to swim in, with very little risk of people becoming irritated by harmful pathogens and other contaminants.
Get Rid of Algae
Pool shocking is the best way to get rid of algae and prevent it from developing. The more severe the algae issues, the more shock treatment your pool needs, so it’s best to do the process regularly.
How Often to Shock a Pool
You should aim to shock your pool once every week. That said, if it’s been subject to heavy use or if the water becomes cloudy, foamy, green, or smelly too quickly, you’ll need to do it more often.
For example, during the summer, when pools are used a lot and the sunshine is so strong that it can dull your chlorine faster, you’ll want to shock your pool more often–so, if you’re wondering how often to shock pool in the summer, it’ll likely be about twice a week.
When to Shock a Pool
Here are the times when you should shock your pool and some tell-tale signs that it’s time for some treatment:
Pool Opening and Closing
When you close your pool during the winter, bacteria and algae build up in the water. So, once you open it back up, shocking it should be one of the first few things you do. You also want to shock your pool before you close it for the season. This gives you the chance to clean and inspect your pool and make it easier during spring or summer to get it back in good swimming condition.
Following Heavy Use
When a lot of people use your pool, the chlorine has to work extra hard to keep it all clean. This is because people introduce a ton of organic contaminants into the water, such as oils, sweat, products, and more. After heavy use, chlorine depletes more rapidly, so you need to shock your pool to get its FC levels back up.
After Long Periods of Sun and Rain
During extended periods of sun and rain, your pool’s chemical makeup can be upset. Hot weather can lead to bacteria growth and the impediment of chlorine, while rain can load the pool with contaminants and dilute the pool water. Shocking your pool becomes necessary after these weather conditions.
When You Can Smell Chlorine
Many people assume that when their pool smells of chlorine, it’s a good thing that means the chemical is working. But the opposite is happening–a strong chlorine smell is indicative of high levels of CC, which could cause red eyes, itchy skin, irritation, and respiratory issues. If your pool gives off a really strong odor, it’s time to shock it.
After a Change in Pool Temperature
If you have a heated pool or one that’s under the sun all day, it will experience changes in temperature that could eat up FC and allow microorganisms and bacteria to flourish. In this case, you’ll need to shock your pool more often.
Learn How to Shock a Pool Easily
Shocking a pool is easy, and you can do it in six simple steps. Learn how best to shock a pool from the Pool Care Guy, and get more tips on how to keep your pool clean and clear–all the time!
Hi, I’m Matt Harper, the founder of poolcareguy.com, a site I started with one simple mission: to help people around the world clean and take care of their pools and hot tubs on their own, without the hassle.
I’m not a professional pool cleaner and don’t have any formal training, I’m just an average guy who loves hanging out by his pool and hot tub and taking care of it. After many years on the job, I’ve become quite good at it.
On this website I will be teaching you absolutely everything I know about pools and hot tubs.