In recent years there has been a growing interest in chlorine free swimming pools in the UK. We look at some of the alternatives to chlorine.chlorine-free-pools

Why do people want to be chlorine free?

As with most popular trends, there are a number of reasons why people would prefer to have a no-chlorine or low-chlorine pool.

Many people would like to live more eco-friendly lives and that would certainly include using less chlorine in their pool. Chlorine is a common element on Earth but it is not found naturally in its pure state.

A little chlorine is essential to life but it can become dangerous at high concentrations. Using less chlorine in your pool certainly would make it more eco-friendly.

Some people don’t like the smell, stinging eyes and skin irritation that is associated with a chlorinated pool, although most of these symptoms come from the chloramines that are produced when chlorine breaks down.

Some people believe that even at the low levels of concentration that are found in a pool, chlorine isn’t great for young children and some people would just like to reduce their pool chemical bill.

In any event, the demand for chlorine free or low-chlorine pools is on the increase and there are ways that this can be achieved.

What are the options for a chlorine free pool?

Salt-water pools are sometimes thought of as being chlorine free but this isn’t actually true.

You don’t physically add chlorine to a salt water pool but that is because the pool makes it’s own chlorine through electroloysis.

If you want to seriously reduce the amount of chlorine in your pool, you need to look at another sort of technology; UV treatment systems.

UV water treatment systems – such as Triogen – pass the water that is being pumped around your pool through a steel cylinder that contains a UV lamp.

There are virtually no microorganisms that are immune to UV and so chlorine levels can be reduced by almost two thirds – down to 0.5ppm – which is about the same level as you find in drinking water. That means that a UV treated pool is using far less chemicals and therefore will also need less backwashing, which will help reduce water and heating costs.

The UV radiation is also a highly efficient natural disinfectant that kills bacteria, viruses and moulds by damaging their DNA. Low doses of chlorine are left in UV treated systems just to provide a back-up level of disinfectant.

A completely chlorine free pool can be achieved by a combination of UV treatment and hydrogen peroxide. Hydrogen peroxide, like chlorine, is an oxidizer, but nowhere near as powerful.

A chlorine free pool needs about 30-40ppm of hydrogen peroxide and it is not compatible with DE filters.

Reducing chlorine use with a FROG.

FROG supply dosing systems for both pools and spas, their patented mineral technology destroys bacteria while reducing chlorine or bromine use by up to 50%.

The Pool FROG Mineral Reservoir contains an EPA registered mineral formula and fits inside the Cycler. The Cycler acts as a “water treatment centre” and controls the flow of water through the system without the need for extra plumbing.

FROG Mineral Products control bacteria and help keep the pH neutral, which reduces chlorine or bromine use by up to 50% and makes the water feel silky soft and look crystal clear.


If you would like to start a discussion on the subject, just use the comment box below. If you’d like help in finding someone who can install a UV treatment system, use the contact buttons at the top right of this page.