How Often Do You Shock a Pool

One of the keys to maintaining your pool is shocking it. It’s not necessary to break out the bad behavior – what we mean here is refreshing your chlorine to keep your pool bacteria-free and clean. No question that this is a good idea, so what we want to know now is how often do you shock a pool.

The experts recommend shocking your pool once a week. I know things get busy, so if you’re not able to do it that frequently, you should shock it at least every other week. This is necessary to keep things balanced and clean, and will save you time and money long-term. However, this shouldn’t be set in stone! The amount of rainfall can increase how often shocking your pool is needed.

how often to shock pool

Lots of people think that swimming pools smell like chlorine, but this isn’t really true. When you are smelling that strong chemical bleach smell in or around the pool, what you’re actually smelling are chlorides. They are the things naturally get into the pool like oils from your skin or sweat combined with chlorine – that’s how the chlorine works to keep the pool clean.

But they can build up, and that is when they start to smell like bleach, and can even hurt your eyes. Shocking the pool will reset the chlorine level so it can continue to do its job. Let’s take a look at how this works.

What is Pool Shock

HTH 52026 Super Shock Treatment Swimming Pool Chlorine Cleaner, 1 lb (Pack of 12)

Basically, pool shock is a balancing chemical, often a form of chlorine, although there are chlorine-free shocks available. When you shock your pool, the chemical you add breaks down the combined chlorine, the chlorimides. This refreshes the free chlorine and gets it ready to clean up some more.

Pool shock comes in both granular and liquid form, so you have some choices as to which is better for you. The granular form is usually stronger and less expensive, so many people go with that. But it’s all about your preference and the strength you need for your pool.

There are non-chlorine shocks, as well. They offer the advantage that the waiting time after use is generally much shorter. Because of the short wait time, this is a good option for use between heavier chlorine shocks, especially if the pool is seeing a lot of use. However, non-chlorine shocks don’t kill algae, so you will also have to deal with a separate algaecide to keep that under control if that’s your main shock choice.

Why You Shock Your Pool

HTH 52026 Super Shock Treatment Swimming Pool Chlorine Cleaner, 1 lb (Pack of 12)

Chlorine is what you might call a sensitive chemical. What I mean by that is it’s a little unstable, which is why it works so well to clean things and kill germs. But that also means that it needs to be maintained and refreshed regularly.

When you swim or play in the pool you are bringing all sorts of stuff with you – oils, sweat, skin care products, even bacteria. Chlorine combines with these unwanted things and neutralizes them. When you shock the pool, it breaks up the chlorimides and gets rid of things that are contaminating your pool, and that raises the level of free chlorine so it can do its job without lowering the pH of your pool. 

When you’re using your pool regularly, you should also be shocking your pool regularly. This keeps the chlorimides, algae, and bacteria from building up before they become a problem. If you wait until you can see or smell them, it’s going to take a lot more work to get rid of them than it would be if you had prevented them building up in the first place.

How Often Do You Shock a Pool

HTH 52026 Super Shock Treatment Swimming Pool Chlorine Cleaner, 1 lb (Pack of 12)

As I mentioned above, it’s a good idea to get in the habit of shocking your pool once a week for regular maintenance. Beyond that, there are other times that you will want to shock it.

The weather can affect the chemistry of your pool. It’s necessary to shock it after rainstorms. Rainwater often changes the chemical balance of your pool. The rain can also bring in other things like debris, algae spores, and bacteria that you will want to get rid of with a shock treatment.

When the weather is hot and sunny it’s perfect for bacteria, which are not perfect for swimming pools. It also means that the chlorine dissipates more quickly. Shocking after hot weather keeps the chlorine active so those bacteria don’t take up residence.

Lots of bodies in the pool means the chlorine is working extra hard and getting combined with lots of sweat, sunscreen, cosmetics, and all sorts of stuff that people bring with them into the water. This means lots of those chlorimides. After pool parties or other heavy use days you should shock the pool to get rid of them.

Accidents happen, even when you’re careful, and so it’s entirely possible that you may end up with blood or other things getting in the pool, especially if there are small children using it. It’s really critical to shock after any bodily fluid related incidents. 

Another time that you should shock your pool is at the beginning and end of the season. This starts things off right and gets it ready to use. Shocking at the end of the season means it’s easier to get it ready to go next year.

When to Shock Your Pool

We know that chlorine is sensitive, and that affects the when you shock the pool as well. Generally, it’s best to do it after dark. During the day, the UV rays from the sun quickly burn off the chlorine so it doesn’t have a chance to get to work breaking down the chlorimides and resetting the free chlorine level. 

You should also time it so that you’ve already cleaned any debris out of the pool and you’ve got the pump running to circulate the shock in the most effective way. 

Is Shocking Your Pool Dangerous

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These are some serious chemicals, and so it’s super important not to shock the pool when it’s in use! Since swimmers should wait anywhere from 8 to 48 hours, depending on the shock, after the process before getting in the pool, it’s a good idea to shock your pool after you’re done using the pool for the night.

Also, remember to protect yourself. Wear gloves, eye protection, and clothes that you don’t mind getting stained if you spill it on them. If you do get the chemicals on your skin, rinse them off as soon as possible.

Add the shock carefully and be sure there is no wind or that it’s blowing away from you. You don’t want to breathe the fumes if you can help it, as chlorine can irritate your lungs.

Don’t mix pool shocks, or store opened shock. And, of course, always follow the instructions on the package carefully.


Everyone loves a sparkling clean pool. Now we know how often you shock a pool in order to keep it that way. Regular maintenance means that your pool stays safe and clean – and saves time by preventing things that take in-depth cleaning to get rid of.

Swimming pool chemistry can take a little time, and maybe a little math, but keeping up with it on a regular schedule is key to peak swimming pool fun!

HTH 52026 Super Shock Treatment Swimming Pool Chlorine Cleaner, 1 lb (Pack of 12)

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