Can I use bleach in a spa instead of chlorine? (Problems with bleach in a spa)

Common questions about using household bleach as a spa sanitiser instead of chlorine. Find out why we don't recommend this.

Can I use bleach in a spa instead of chlorine hero

You may be wondering if it is safe to use household bleach as a sanitiser or cleaning product in your spa pool or swim spa?

In this article we'll address common questions about this and explain the best types of sanitisers and cleaning products to use in a spa pool.

We cover:

Can I use bleach in my spa instead of chlorine?

No, we do not recommend using bleach as a sanitiser for your spa water for a number of reasons.

  1. The chemical makeup of bleach is completely different from chlorine sanitisers that are specifically designed to effectively sanitise your spa water
  2. The concentration of household bleach is different which means you would be guessing as to the correct amount of bleach needed to correctly sanitise your spa water and kill bacteria.
  3. If you put too much in, you’ll upset your spa water’s chemical balance which can lead to irritation for bathers for eyes, skin and respiratory system. This can also cause damage to components in your spa such as the headrests, spa shell and other components such as jets and waterfall bodies.
  4. In some cases household bleach has other ingredients added to it such as calcium and fragrances which can react with your spa water, introducing oils that can contribute to the formation of scum or other unwanted byproducts in your spa water. These will affect your water clarity.
  5. Household bleach is not stabilised, which means it can quickly be burned off when exposed to the UV rays of the sun, before it has time to effectively sanitise your spa water.

What kills bacteria in my spa?

The best way to kill bacteria in a spa is with an approved sanitising product that is specifically designed for spa water.

Sodium Dichlor (Chlorine) in granular form is the most powerful and safest type of sanitiser to use in your spa or swim spa. This is not dangerous goods so it is easy and affordable to ship. Make sure the formula is sodium dichlor NOT calcium hypochlorite which is for swimming pools only.

If you want to steer away from chlorine sanitiser altogether, you can also try hydrogen peroxide, like the Spa Store brand or the Poppits brand. These products are dangerous goods and come in a liquid form - they need to be handled with care.

What kills bacteria in my spa?

The best way to kill bacteria in a spa is with an approved sanitising product that is specifically designed for spa water.

Sodium Dichlor (Chlorine) in granular form is the most powerful and safest type of sanitiser to use in your spa or swim spa. This is not dangerous goods so it is easy and affordable to ship. Make sure the formula is sodium dichlor NOT calcium hypochlorite which is for swimming pools only.

If you want to steer away from chlorine sanitiser altogether, you can also try hydrogen peroxide, like the Spa Store brand or the Poppits brand. These products are dangerous goods and come in a liquid form - they need to be handled with care.

Is there any evidence that bleach is effective at killing germs and viruses in a spa?

Although bleach does have a chlorine component to it, there is no concrete evidence to suggest that bleach is an effective disinfectant against germs or bacteria in a spa. Bleach can throw off the water's pH levels, which could lead to skin irritation and other problems.

The strength of household bleach is much more diluted than dedicated spa sanitiser. It can provide some effectiveness at killing bacteria, but it will be a shot in the dark for you to get the dosage correct for your spa. You may also introduce other unwanted ingredients to your spa water than may have been introduced to the household bleach product.

As we discussed above, bleach can upset the pH level and total alkalinity in your spa water, making it more difficult to maintain your water clarity and keep bacteria at bay.

It just simply is not worth the trouble!

Will using bleach in a spa damage the plumbing system or do anything else harmful to the spa equipment?

Using bleach could lead to an pH levels that are too high, which could cause damage to the body and equipment components in your spa.

Are there any disadvantages or risks associated with using bleach in a spa?

There are a few risks associated with using bleach in a spa. First, bleach can be dangerous if it comes into contact with eyes or open wounds. Second, using bleach could upset the water's pH levels, which could lead to skin irritation and other problems. Additionally, bleach used incorrectly can also cause metal components in the spa equipment to corrode over time.

Can I shock my chlorine spa with bleach?

We do not recommend using bleach as a shock product in your spa. It can upset your spa's delicate water balance, causing your pH to drop too low meaning your water becomes acidic and corrosive.

The same concerns that we have already discussed apply to this question.

So far, we have spoken about using bleach as a daily sanitiser and we have recommended against it for the reasons explained above. Another commonly asked question about using bleach in a spa, is whether it is suitable to be used as a shock product in larger doses more infrequently to kill bacteria in a spa.

  1. The concentration of chlorine in bleach is significantly lower than that found in a dedicated spa shock product.
  2. Different types of household bleach products may come in different concentrations, making it hard to know how much to add. (Not enough and it will be ineffective. Too much and it will throw off your chemical balance)

Can you use liquid chlorine in a spa or swim spa?

No, it is not recommended to use liquid chlorine as either sanitiser or shock in your spa.

If you are referring to liquid chlorine that is used as a sanitiser for swimming pools, then this has a different concentration than what is needed in a spa pool. Furthermore, it is not designed to operate effectively in the warmer water temperatures found in spas, hot tubs and swim spas.

The best chlorine sanitiser for spas and swim spas is granular sodium dichlor. Two popular sodium dichlor products are the Spa Store branded chlorine or BioGuard Armour.

Can you use bleach to clean a spa pool or swim spa?

No! The harsh chemicals in bleach can damage the components in your spa. It is recommended to use a dedicated spa cleaning product like BioGuard Squeaky Clean.

Is household bleach different from what you use in a spa?

Yes, household bleach has a different chemical makeup and a lower concentration of chlorine and should not be used in spas or swim spas in place of specific spa chlorine.

What can I use instead of chlorine in my spa?

If you’re looking for an alternative to chlorine for sanitising your spa, the good news is that there are alternatives available, allowing you to have a chlorine free spa pool

One thing to bear in mind is that chlorine is one of the most effective sanitising agents at killing bacteria, so using a chlorine-free alternative may require more maintenance.

Hydrogen peroxide is an excellent alternative to chlorine. Read more about the benefits of hydrogen peroxide in this detailed article.

Can I use bleach to clean my spa filters?

No, it is not recommended to use bleach to clean your spa filters as it weakens the filter media, reducing the lifespan of your filters.

Can I use Dettol disinfectant to clean my spa filters?

We also don't recommend using Dettol or any other disinfectant to clean your spa filters as it can cause issues with water quality. It can potentially interact with your sanitiser preventing it from working properly, it can also adjust your water balance and reduce the life of your filters.

Got more questions?

Talk to us on live chat, or email us your spa chemical questions and we'll be happy to help!

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