What to use instead of chlorine in a spa pool (Products, pros, cons and more)

If you’re looking around for a spa pool or swim spa and have heard bad things about chlorine, you may be searching for an alternative to chlorine sanitisers and treatments.

The good news is that by using alternative chemicals, it is possible to have a chlorine-free spa pool.

The ‘other’ news is, in our 40 years of selling spas and swim spas, we have not come across a sanitiser as effective as killing bugs as chlorine. Learn aboutspa sanitisers with their pros and cons

This is not to say that you can’t take care of your spa water with chlorine-free alternatives, it's just that you are going to spend more time and effort keeping your spa water clean and clear.

If the extra effort doesn’t put you off and you’re still interested in a chlorine free spa, keep reading to learn about the options available to you.

In this article, we’ve used brand names not affiliated with Spa World™ or Vortex Leisure Pty Ltd, the parent company of Spa World™. You can see the list of the brand owners at the bottom of this article. All information, including pricing and product details, was accurate at the time of writing (10 February 2021) and may change without notice.

Can you have a chlorine-free spa pool?

Yes, you can certainly have a chlorine-free spa pool, swim spa or plunge pool.

The main alternatives to chlorine for spa sanitising are:

• Hydrogen peroxide
• Enzyme treatments

Bromine and silver are also used in spa sanitisers, although it's not as common.

There are a range of products you can choose from that use hydrogen peroxide or enzyme treatments.

Keep reading to learn more about alternatives to chlorine in spas, pools and swim spas.

What can I use instead of chlorine in my spa?

Wondering what chlorine-free spa sanitisers and treatments are available in New Zealand?

Top chlorine-free spa chemicals in New Zealand:

• Poppits^® Chlorine Free Spa Sanitiser
• Silver Cove^® Pool Sanitiser

View the full range of chlorine-free spa sanitisers, treatments and chemicals on the Spa Store^® website.

Where can I buy Poppits^® Spa Sanitiser?

Poppits^® is one of the world’s most popular chlorine-free water sanitisers. Poppits^® products have been used in spas in New Zealand and Australia for over 40 years. Learn more about Poppits Chlorine Free Spa System in this article.

You can buy Poppits^® Chlorine-free Spa Sanitiser at Spa Store^®. You can also find it for sale at Direct Pool Supplies^® and Swimart^®, among others.

Now you know a bit about chlorine free spa products, let’s look at some chlorine free sanitising options that can be used to treat your spa water – starting with the most popular, hydrogen peroxide.

Alternatives to spa chlorine: Hydrogen peroxide

Hydrogen peroxide is probably best known as a product that can strip colour from hair. Hence the term; peroxide blonde.

Like chlorine, hydrogen peroxide is an oxidiser (although less effective) so it is good at keeping your pool water clear. It also has antiseptic properties and **so it is good for killing bugs. **

Bear in mind, as an oxidiser it is considered a 'dangerous good' – meaning couriers have to handle it separately from other goods which can add extra delivery costs and time.

Hydrogen peroxide is sold in liquid form for use as a chlorine-free spa sanitisers by a range of suppliers, including Pool Poppits^® and Spa Store. It does degrade in sunlight and so it is best stored in a dark space.

Most suppliers promote Hydrogen Peroxide as part of a complete system which will include a water prep and a weekly super dose additive.

Whilst similar to the efficacy of chlorine, hydrogen peroxide systems (in our experience) can require a little more work. They can also be overwhelmed by heavy bather loads and it is harder to get the water clear once it has gone off. But all in all, this would be our favourite non-chlorine solution.

Verdict: In our opinion, hydrogen peroxide is the best option for chlorine free spa sanitisation but will require a little more effort than chlorine.

Alternatives to spa chlorine: Enzyme treatments

Enzyme treatments can be used as part of a combined water treatment system with either chlorine or bromine.

A popular enzyme spa treatment brand is AquaSpa™. AquaSpa™ states on its packaging that it is a weekly dosage, odour-free and suitable for all spa types and equipment.

Enzymes can be useful in reducing the amount of chlorine or bromine needed to be used in a pool or spa.

Why? Well, enzymes' primary purpose is to degrade or break down non-living organic compounds. In doing so, they reduce the work that the chlorine or bromine sanitiser has to do, meaning people use less of it.

However, enzymes are not great at killing living organisms, which is why they need to be used alongside chlorine or bromine. Also, there is no simple test to show how much of the treatment is present in the water (unlike tests for chlorine and bromine). Therefore, it is hard to gauge when you need to add more.

To underline the above, we did a little experiment. Below left is a photo of a spa after 2 weeks of an enzyme treatment with no chlorine used. Below right, is a picture of the same spa 15 minutes after adding a super dose of chlorine.

As you can see, the spa’s water had gone quite green when just using the enzyme treatment - likely due to algae growth.

However, the chlorine cleared the water very quickly. Probably more quickly than if we had not first been treating the spa with the enzyme treatment.

Verdict: Whilst a useful supplementary treatment, we do not recommend enzyme treatments as a stand alone chlorine alternative because enzymes are not great at killing living organisms and need to be used alongside chlorine or bromine.

Alternatives to chlorine: Silver

Silver water treatment comes in two main forms; liquid and granular. The granular form has the advantage of lasting up to a year when held in a submersible cartridge.

The most popular silver granular cartridge is SimpleSilver™. Simple Silver™ is a viable, stand alone chlorine-free solution if you have low spa use or are fastidious in your spa cleaning routine – including showering before using your spa. Learn more about that in this article.

We have had customers using SimpleSilver™ for years in New Zealand and many love it due to the low amount of maintenance required. However, many have found that like hydrogen peroxide, it lacks the clarifying power of chlorine and can become quickly overwhelmed if the spa is in heavy use. This can necessitate a super dose with chlorine or another form of oxidiser in order to clear the water again.

Simple Silver™ is a viable, stand alone chlorine-free solution if you have low spa use or are fastidious in your spa cleaning routine – including showering before using your spa. Learn more about that in this article.

Be aware that silver and other mineral-based options, cannot be used in conjunction with sanitisers that contain bromine as the minerals will stop working.

Verdict: Silver is a viable alternative to chlorine if you have low spa use (a couple of people 3 to 4 days a week) and are fastidious in your spa cleaning and maintenance routine.

Alternatives to chlorine: Bromine

We’re often asked by our customers if bromine or chlorine is better for spa pools.

As mentioned above, in our 40 years of selling spas and swim spas, we haven’t come across anything that works as well as chlorine for killing bugs in water. While bromine is a very good sanitiser - it has its limitations, as we explain below.

Bromine has a similar oxidising effect as chlorine (it is actually an ioniser but we are splitting hairs). Therefore, it not only kills bugs but it also clears the water.

Bromine doesn’t have the immediate impact that chlorine does but tends to last in the water longer. For this reason, some spa sanitiser manufacturers combine the two. A very popular bromine-chlorine combination sanitiser is Bioguard Armour.

You can also buy bromine tablets and many customers like to put these in a floating dispenser or ‘floater’ in their spa.

We strongly recommend that you don’t do this as it tends to concentrate the bromine on the surface of the spa’s water and can damage the acrylic shell around the spa’s water line, damage which is not typically covered under the spa warranty. It can also harm jets, headrests and heaters.

Lastly, bromine does not do so well in hot water – which if course most spas have. Therefore, bromine is more widely used in swimming pools, making it a great option for swim spas if they are kept at or below around 32 degrees celsius.

Verdict: Bromine is a very good sanitiser but it shares many of the properties of chlorine that some people do not like such as a strong smell, it can dry your skin and cause itchy eyes. It is better suited to cooler water temperatures.

In summary

We hope this article has helped you understand more about alternatives to chlorine in spas, the products available and which is best for you.

As discussed, chlorine is the most popular water sanitiser for pools and spas and is safe, effective and easy to use. There are also some excellent chlorine-free sanitisers available. It all depends what best suits your needs.

For more information on spa sanitisers and keeping your pool clean and healthy, please contact us or visit your local Spa World showroom. We’re happy to help!

DISCLAIMER: The following registered trademarks are owned by companies not affiliated in any way with Spa World™ or Vortex Leisure Pty Ltd – the parent company of Spa World Ltd:

Poppits^® Spa Sanitiser trademark is owned by Waterco. Bioguard^® Armour Spa Sanitiser trademark is owned by Biolab – a KIK Custom Products Company Zodiac^® Spa Chlorine trademark is owned by Fluidra Group Australia Pty Ltd SimpleSilver™ trademark is owned by SimpleSilver Direct Pool Supplies^® Swimart^®

Affiliations: Vortex^® Spas, Fisher™ Spas, Spa Store^® and Spa World™ are trademarks owned by Vortex Leisure Pty Ltd.