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Is Hot Tub Shock the Same as Chlorine? (Complete Guide)

Hot tub chemicals can be a bit confusing. We hear terms like shock, sanitizer, and chlorine. So, I get it if you’ve wondered: is hot tub shock the same as chlorine?

Hot tub shock is not the same as chlorine sanitizer. Hot tub shock, which can be chlorine-based, is an oxidizer that has higher chemical strength and is designed to reactivate sanitizers such as chlorine. While most hot tub shock is chlorine-based, there are others that are non-chlorine-based.

So you can have both sanitizer and shock that are made from chlorine.

Or you could not use chlorine at all and use bromine sanitizer and a non-chlorine shock. But either way, you need both sanitizer and shock.

Both shock and sanitizer are needed to keep your hot tub sanitary and clean but should not be used at the same time.

In this article, we’ll explore the difference between sanitizer and shock for a hot tub and the difference between chlorine and non-chlorine-based shock. But we will also look at how often you should shock your hot tub and a lot more.

Let’s get going.

Ready to Spend Less Time On Maintenance and More Time Enjoying Your Hot Tub?

Let’s face it. Balancing the water, cleaning filters, dealing with rashes, and trying to figure out which chemicals to buy and add can make you feel more like a chemist than someone who just wants to relax after a long hard day!

That’s exactly why The Hot Tub Handbook and Video Course is so valuable!

This is from Matt over at Swim University and he developed it for people looking to save money, time, and frustration. His tips on chemicals can save you $100/year just by making sure you buy only what you need.

So if you’re ready to stop being confused or frustrated with your hot tub and start spending more time in it, check out The Hot Tub Handbook and Video Course.

Just click that link to learn more on their website.

shock same as chlorine lg

What is the difference between sanitizer and shock for a hot tub?

The biggest difference is that shock has a higher dose of chemicals and is designed to reactivate sanitizers. Sanitizer kills bacteria and purifies the water, while shock removes non-bacterial organic contaminants and other matter from spa water.

So make no mistake; you need both.

Shock also turns chloramines and bromamines back into their original state, making them more effective and consequently helping with the process of sanitation.

Bromamines and chloramines are bad because they deceive the test strips into thinking that the water still has the correct amount of chlorine or bromine when in point of fact, it is low or has none at all.

Without the use of shock, the sanitizers eventually become too weak to do their job. This is why in addition to using sanitizers, hot tubs are shocked weekly or after heavy use.

Shocking a hot tub means that a large dose of oxidizer is applied to it.

The purpose is to break down bacteria, organic matter, and other contaminants so that the water can be clean and safe. An oxidizer is a chemical that takes electrons from the organic matter it encounters. In effect, it breaks them down.

There are chlorine-based (dichlor shock) and non-chlorine oxidizer (potassium peroxymonosulfate).

They are available in liquid and powder forms. Chlorine-based shock is also available in granular form. Non-chlorine-based shock is also available in the form of salt. And there is also liquid chlorine. Chlorine-based shock treatment is the most common.

Chlorine and bromine are the most common types of sanitizers used in hot tubs. Naturally, each has its pros and cons.

Interested in learning more about oxidizers?

Check out a recent article where I get into it in more detail. In it, I explained what hot tub shock is and if it’s the same thing as an oxidizer, and when you should shock your tub. I also spoke to if you can shock a hot tub too much. And I revealed the difference between an oxidizer and a sanitizer.

Just click the link to read it on my site.

What is the difference between chlorine shock and non-chlorine shock?

Chlorine shock dissolves quickly and has a neutral pH. It is also effective for restoring chlorine or bromine sanitizer levels. Non-chlorine shock has a lower pH. It is effective, but not as much as chlorine shock, and it can also leave the water cloudier.

Both are oxidizers aimed at breaking down bacteria, organic matter, and other contaminants. However, chlorine shock is more effective. But, it leaves a strong odor, and you have to wait for 24 hours.

Non-chlorine shock (MPS) cannot kill off algae and bacteria.

So, it is not as effective as chlorine. The upside is that you can use the hot tub twenty minutes afterward. It is also a safer alternative because, unlike chlorine shock, it leaves no odor.

But it is pricier than chlorine shock and, when used in large quantities, can raise the hot tub’s total alkalinity.

It has a low pH and also dissolves quickly. And unlike chlorine, it works well under the sun and under extreme heat. Chlorine, on the other hand, is more sensitive to the sun and extreme heat.

So, must you use a non-chlorine-based shock if you use bromine? Check out a recent article I published.

I get into whether it’s okay to use a chlorine-based shock if you’re currently using bromine as a sanitizer and the differences between shocks and sanitizers. But I also shared the difference between chlorine and non-chlorine-based shocks.

Just click the link to read it on my site.

Can I use liquid chlorine instead of shock?

Yes. You can use liquid chlorine instead of shock. Both actually have the same active chemical (unless you’re considering non-chlorine shock). The difference between them is not in what they are made up of but whether they are stabilized or unstabilized.

Liquid chlorine is un-stabilized — it lacks cyanuric acid, which helps it withstand the hot tub heat. It works quickly.

It starts dissolving in the hot tub water immediately because it is already in liquid form. It is also a bit cheaper. Truth be told, liquid chlorine is more suited for pools because it’s concentrated; it’s not what I’d recommend you use as shock.

In fact, over the years, I have owned 4 hot tubs and have had to become pretty familiar with the best hot tub chemicals to use.

Check out my top recommendations right here on my website.

Before you apply liquid chlorine, remove the hot tub’s cover and check the pH level. Leave the cover open for 20 minutes afterward.

Then, you’ll need to wait for 2 hours before you test the chlorine levels to ensure they are safe. Waiting for 24 hours is ideal. So, you may want to apply it after you have finished using the hot tub.

It leaves no residue and does not add calcium or cyanuric to the water. But it has a high pH level.

Is non-chlorine shock effective?

Yes. Non-chlorine shock is effective as it eliminates contaminants in hot tub water. However, it does not kill bacteria and algae growth, and it does not raise the level of chlorine. As such, its effectiveness is more limited than the chlorine-based type of shock.

Let’s look at the specific ways in which it’s effective.

It helps in improving sanitizer efficiency because when you use non-chlorine shock, you free up your sanitizer to do its main job, killing off bacteria, resulting in less sanitizer being used.

It also removes oils, lotions, deodorant, dead skin cells, leaves, or detergent from the hot tub, that way, it prevents or reduces foaming and reduces the strain on the filters.

Several hot tub chemicals are indispensable if you want you and your loved ones to have fun without worrying about catching anything in the water.

Find out the ones you really need. I’ve made a list of the best hot tub chemicals I have been using. Here are my top recommendations.

Let’s get back to non-chlorine shock.

It helps to restore water clarity fast. If the hot tub’s chlorine levels, pH, and alkalinity are okay, it will help make the water clearer, especially when they are caused by factors I mentioned earlier.

It can help regenerate bromine. If your hot rub runs on bromine, non-chlorine shock shocks the bromide ions (spent bromine) and forms new bromine, increasing the bromine level.

Say you’ve added chlorine or bromine to your hot tub, how soon can you use it?

This is the theme of a recent article I published where I shared how long you have to wait after adding chlorine and whether you can get into the hot tub faster if you use bromine instead of chlorine.

I also shared safe levels for bromine or chlorine in a hot tub. And I revealed what happens if the chlorine level is too high in a hot tub.

Just click the link to read it on my site.

Does non-chlorine shock raise alkalinity?

Yes. When applied in significant quantities, non-chlorine shock will raise alkalinity in your hot tub. Total alkalinity is a measure of how well the water can neutralize acids. Now, pH and alkalinity are related. So, non-chlorine shock will also raise pH levels.

It’s also good to note that some non-chlorine shocks are buffered to make their pH neutral, while others are non-buffered and are thus acidic.

So, pay close attention to the type you’re using and ensure you measure alkalinity and pH levels after using non-chlorine shock before you soak to get both at the recommended range.

It’s vital to check both regularly because of the health of those using the hot tub, the longevity of the hot tub equipment, and water quality.

I bet when you first thought of buying a hot tub, the last thing you thought you’d need to learn about were chemicals.

But hot tub chemicals are indispensable if you want you and your loved ones to have fun without worrying about catching anything in the water. So, I’ve made a list of the best hot tub chemicals I have been using.

Here are my top recommendations. Check them out.

How often should I shock my hot tub?

You should shock your hot tub weekly. However, you can shock it twice a week if it is being used more frequently or if a lot of people are using it. Not shocking it can lead to bromamines or chloramines building up, which can give false readings on test strips.

So, while I do it weekly, if my teenage daughters have a sleepover and the hot tub is filled with kids all night, you can bet I’m shocking it the next morning!

I like to check the water chemistry after every soak.

So, unless it is way off, I like to adjust the chemicals when I get out. That way, it’s ready for next time. Then, at the end of each week, I add some shock.

To shock your hot tub, use chlorine-based or non-chlorine-based shocks. Truth be told, chlorine-based shock is more effective at cleaning the hot tub, but some people find it harsh on the skin.

It’s vital to shock the hot tub consistently. If you don’t, the water can get gross and murky looking, and it becomes a health danger to users. Just pour in about 1/4 cup, turn on the circulation pump via the jets, and leave the cover off for about 20 minutes.

It’s not enough to use sanitizers because over time, their power becomes weakened, and they become inert. Shock helps reactivate them.

What does adding shock to a hot tub do?

Adding shock to hot tub water ensures that it breaks down organic waste contaminants, which cause odor, and cloudy or foamy water. It also reactivates sanitizers making them do their job better. In a nutshell, shock makes your hot tub clean and sanitary.

But aren’t sanitizers enough?

No, they aren’t because over time, sanitizers become less effective as they destroy contaminants. In fact, they bond with them to form chloramines and bromamines, which could deceive test strips into giving false readings.

So, tests could indicate there is still some sanitizer when in fact, it could be very low or non-existent! Imagine the danger to the users if the hot tub is not being shocked consistently.

Both sanitizing and shocking are needed. Sanitizing removes bacteria and viruses, while shocking removes organic matter and reactivates the sanitizer, making the latter more effective.

When your hot tub is shocked, it converts the chloramines back to chlorine if you use chlorine, and it converts bromamines back to bromine if you use bromine.

But note that if you use a non-chlorine oxidizer and bromine, the shock does activate bromide ions, but they have no cleansing power.

Having owned 4 different hot tubs over time, I know a thing or two about shock, in fact, about all the chemicals you need to keep your hot tub in the best shape.

Here are my top recommendations.

Is all chlorine the same and can I add any type of chlorine to my hot tub?

Chlorine is a common sanitizer used in hot tubs to maintain water cleanliness and prevent the growth of bacteria and algae. However, not all chlorine products are the same, and it’s important to choose the right type for your hot tub. Here are some key points to consider:

  • Chlorine forms: There are different forms of chlorine available, including chlorine granules, tablets, and liquid.
  • Stabilized chlorine: Some chlorine products contain stabilizers like cyanuric acid, which help protect the chlorine from degradation due to sunlight exposure.
  • Chlorine concentration: Different chlorine products have varying concentrations of available chlorine, typically measured in percentages.
  • Compatibility: Not all types of chlorine are compatible with hot tubs. Some chlorine products are specifically designed for pool use and may not be suitable for hot tubs.
  • Chlorine feeder: If your hot tub has a chlorine feeder, it may have specific requirements regarding the type and form of chlorine to be used.

It is essential to follow the manufacturer’s recommendations and instructions provided with your hot tub.

Adding the wrong type of chlorine or using improper amounts can lead to water imbalances, skin irritation, and equipment damage. Consult your hot tub’s manual or a water chemistry professional to determine the appropriate chlorine product and dosage for your specific hot tub model and water conditions.

Conclusion

We covered a lot in this article. We learned about the difference between sanitizer and shock for a hot tub and the difference between chlorine and non-chlorine shock.

Then, we looked at whether it’s feasible to use liquid chlorine as shock. We also explored the effectiveness of non-chlorine and whether it raises alkalinity.

We found out how often you should shock your hot tub. Lastly, we wrapped things up by looking at the effect of adding shock to a hot tub.

Ready to Spend Less Time On Maintenance and More Time Enjoying Your Hot Tub?

Let’s face it. Balancing the water, cleaning filters, dealing with rashes, and trying to figure out which chemicals to buy and add can make you feel more like a chemist than someone who just wants to relax after a long hard day!

That’s exactly why The Hot Tub Handbook and Video Course is so valuable!

This is from Matt over at Swim University and he developed it for people looking to save money, time, and frustration. His tips on chemicals can save you $100/year just by making sure you buy only what you need.

So if you’re ready to stop being confused or frustrated with your hot tub and start spending more time in it, check out The Hot Tub Handbook and Video Course.

Just click that link to learn more on their website.


Image by Dyah Kusumaningrum from Pixabay and Image by Adriano Gadini from Pixabay

Jeff Campbell