how to shock a hot tub for the first time

Are you ready to hear something shocking?

It is impossible to create long-term hot tub cleanliness with only sanitizer.


Yes, sanitizer eventually loses its potency, allowing bacteria and other contaminants to run rampant in your hot tub. For this reason, smart hot tub owners shock their hot tubs to keep them clean for long periods.

If you’re getting irritated with bacteria, smelly water, or imbalanced chemical levels, it might be time to shock your hot tub!

Let’s dive in and find out the best way to do it!

Why Do I Need To Shock My Hot Tub?

Now before tossing in your corded toaster to try and shock your hot tub, know that the process of shocking has to do with chemicals. There are plenty of reasons why you should shock your hot tub water, including:

Getting Rid of Organic Contaminants

We hate to break it to you, but your body is covered in organic contaminants.

Each time you take a dip in your hot tub, you leave behind dead skin cells, sunscreen, makeup, hair, lotion, and anything else you have on you.

While you can reduce the levels of organic contaminants that you bring into your spa by rinsing off before your soak, it is near impossible to completely rid your body of them. And over time, they build up in your hot tub water. That is why it is advisable to shock your hot tub in order to clean it.

Removing Chloramines & Bromamines

If you’ve ever sat around in a public pool or hot tub, then you’re probably familiar with that strong chlorine smell.

However, it’s not the chlorine itself giving off the scent, but a byproduct of that chlorine known as chloramines. When chlorine kills bacteria and gets rid of contaminants in your hot tub or spa, it produces a waste known as chloramines. The smell eventually fades away as chlorine dilutes in the water, but it can take a while.

To remove chloramines, people often use the shocking method. Not only can this help eliminate that chlorinated odor, but it can also help you breathe much easier when you’re soaking.

Some people use bromine as their primary sanitizer, and just like chlorine, bromine produces a unique waste product known as bromamines. While bromamines don’t have the same level of toxicity as chloramines, you should still shock your spa to get rid of them if you want to avoid that bromine smell and harshness.

Visit our Bromine vs Chlorine Hot Tub guide to decide which of these chemicals would work best for you.

Killing Bacteria

Of course, there are bacteria in your hot tub water, which can cause slight discoloration if left unmanaged. If you’ve ever seen a pink hue in your hot tub water, you’re dealing with bacteria.

While many kinds of bacteria are harmless, other, more dangerous kinds can cause illnesses if not kept under control. These types include Nontuberculous mycobacteria, Legionella, and Pseudomonas dermatitis. From lung problems to skin problems and beyond, it is essential to rid your spa of these contaminants in order to maintain your health.

Spa shocks can provide your tub with the boost it needs to kill anything that shouldn’t be in there.

Hot Tub Shock Treatment

There are many types of shock out there, including calcium hypochlorite, dichlor, lithium hypochlorite, and non-chlorine shock.

We’re going to help your figure out which type of shock is best for your needs.

Note that the process is pretty much the same in terms of time and effort no matter what spa you’re working with, though you may consider using different chemicals based on your spa’s design and whether or not the treatment you want to use is compatible.

How To Shock A Hot Tub With Chlorine

Chlorine shock is one of the most popular types of shock out there.

You use it less often than you would a non-chlorine shock due to its strength.

To shock your hot tub using a chlorine shock, start by removing the cover and ensuring your pH level is correct. It should be somewhere between 7.2 and 7.6.

Next, turn your water circulation on to make sure you have water running through the system.

Take your chlorine shock and measure it out according to the manufacturer’s instructions. Slowly add your chlorine shock to your hot tub and keep the cover removed for at least 25 minutes.

How To Shock A Hot Tub With Bromine

To shock your bromine hot tub, you will use a non-chlorine shock instead.

One thing to note about non-chlorine shock is that it does not work as a disinfectant the way chlorine shock does. Instead it uses potassium peroxymonosulfate, a unique ingredient that effectively oxidizes a hot tub and removes unwanted contaminants.

Plus, it activates free bromine to help keep your water clean for more extended periods.

To shock your spa using a non-chlorine shock, follow the same instructions that you would with a regular chlorine shock.

How To Shock A Hot Tub With Bleach

Many people ask us how to shock a hot tub with bleach and if it is even possible.

The great news is, you can shock hot tubs with bleach, as long as it is of the non-scented variety and does not use any special additives.

However, the thing to note about bleach is that its pH level is through the roof at 13, meaning it will dramatically increase the pH level in your spa water. For this reason, many hot tub owners prefer to stick to Dichlor (which we will discuss below).

The best way to determine how much bleach you need is by using test strips. However, if you don’t have test strips and you want to take a wild guess, keep this formula in mind:

One cup of 5% strength bleach raises a 300-gallon spa’s chlorine level by 10ppm.

How To Shock A Hot Tub With Dichlor

Dichlor is a unique type of shock, as it is made with the active ingredients that you’ll find in most spa shock brands.

The beauty of Dichlor shock is that you can put it into your spa water without having to dissolve it beforehand. But, of course, make sure to follow the instructions the manufacturer provided in the product manual before tossing a big cup in.

Dichlor is a stabilized compound that can hold its own with heat, making it the perfect shocking treatment for spa water. Same as the directions above, use the amount of shock that the manual says is okay to use and allow your hot tub to sit without its cover on for at least 25 minutes after you’ve added your chemicals.

How Often To Shock Hot Tub

You can use spa shock at least once every week. Many hot tub owners use it on a regular basis as part of their spa maintenance routines.

However, there are a few reasons why you might consider breaking your normal cycle and adding spa shock treatment ASAP, including:

  • You have not treated your hot tub in a long time
  • You have been using your hot tub heavily
  • If the “Total Chlorine” level is higher than the “Free Chlorine” level (you can determine this with a test kit

Spa shocks are MPS-based, meaning you won’t find any added sanitizer in them. Like we said before, you should wait for at least 20 minutes before you enter your spa after shocking it. Some say you should wait anywhere from 12-24 hours, though those people are most likely referring to pool shocks, which are far stronger.

Essentially, you can shock your spa before you throw your backyard party and not have to worry about a thing!


Can You Over Shock A Hot Tub?

Yes, you can add too much shock to your hot tub. To make sure you add the right amount of shock treatment to your spa, you must check the chlorine levels beforehand. Also, you should not be shocking your hot tub more than once per week.

If you over-shock your spa, don’t worry. It’s not the end of the world. You just have to wait a bit longer and continually test your water until the chemical levels are balanced and safe to go in.

Can I Use Pool Shock In My Hot Tub?

No, you should never use a pool shock treatment in your hot tub. Doing so is one of the best ways to mess up the pH balance in your spa. If you have an imbalance of pH in your spa, you could damage the internal components, which could cost you hundreds or more in repairs or completely destroy your spa.

How To Shock A Hot Tub For The First Time

If you’re shocking your hot tub for the very first time, follow these steps:

  • Make adjustments to your pH level so that your water is anywhere between 7.4 and 7.6.
  • Remove your spa cover so that chemical fumes can air out once you’ve added your shock.
  • Allow the water to circulate with the jets off so that the water can move around the inside of the tub, though you don’t agitate it too much.

  • Following the manufacturer’s instructions, determine how much shock you must add to your hot tub.
  • Carefully add the treatment to your hot tub. Make sure that it is not raining or windy, as the chemicals could end up blowing or spilling onto your skin or eyes.

Safety is the most important thing to remember. We recommend wearing gloves and safety goggles while you add the treatment to your spa.

Hot Tub Foam After Shock

If you still see foam in your water after shocking it, there are a couple of other products you can use to mitigate it.

Some people like to use spa enzymes, which naturally break down soapy and oily substances. Soaps and oils, which are present on the human body, often contribute to high foam levels in a hot tub. Spa enzymes work by attacking oils and soapy substances to prevent foam buildup.

You may also choose to use a spa defoamer product, which specifically removes foam from water. Spa defoamer does not use any oils, allowing you to use it with any kind of spa sanitizer or solution. If you often have foam appearing in your hot tub, it is a good idea to keep spa defoamer chemicals around.

Both of these products can be found at your local pool and spa store and are compatible with all spas.

Cloudy Hot Tub Water After Shock

From algae blooms to contaminants, there are multiple culprits of cloudy water. If you notice that the water in your hot tub is starting to look a bit cloudy, you can use a shock to take care of it. However, if you still have cloudy water after shocking it, you likely did not add enough treatment to your spa during the shock process.

It is much better to add a high dose of treatment to your hot tub rather than a low dose. Most of the time, if a spa requires a serious cleaning, a low treatment dose won’t have enough power to eliminate the dirty or foamy water that you’re trying to clean. 

See Best Hot Tub Chemicals For Sensitive Skin or Best Hot Tub Chemicals for a list of our favorite products.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *