Chlorine Free Pools: 7 Pool Chlorine Alternatives (Pros & Cons)

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Did you know that not every pool you swim in is loaded with chlorine?

While it’s an excellent sanitizer that kills off nasty contaminants in the water, chlorinated pools can also be harsh for some people to swim in.

An alternative option worth checking out are chlorine free pools. They provide a high level of sanitization, while at the same time being a more healthy option.

Why Have A Chlorine Free Pool?

Wanting to reduce your exposure to chlorine is a smart idea, and many advancements in swimming pool water sanitization have helped pool owners do just that.

But there’s a reason why chlorine has been the pool sanitizer of choice since forever. 

It’s highly effective, safe, budget-friendly, and the best all-round sanitizer due to its ability to totally eliminate dangerous microorganisms and organic debris floating around in your pool’s water.

But some people report allergic reactions to chlorine after a swim – namely itchy skin, burning eyes, and brittle hair. 

These instances are most likely a result of too little chlorine in the water. This results when chlorine gets used up by contaminants, and also because the sun’s UV rays gobble up chlorine over time.

When the pool doesn’t have enough chlorine in it, chloramines start to build up. Chloramines are a gaseous irritant which causes that infamous chlorine “pool smell”, red eyes, itchy skin, and respiratory issues.

If you want to switch over to chlorine free, there’s 2 choices you have to keep your pool clean:

1.  Swap out chlorine for another all-round sanitizer

2.  Pair a different sanitizing system with low levels of chlorine taking a backup/residual cleaning role

Non-Chlorine Sanitizers: 7 Alternatives

If you want to rid your swimming pool of chlorine, you have several alternatives to choose from.

1. Bromine

The sister halogen to chlorine, bromine, is primarily found in sea water in the form of sodium bromide and potassium bromide.

While chlorine uses oxidation to clean the water, bromine uses ionization. This process entails breaking apart the chemical bonds of the contaminants, effectively killing them. 

Keeping your pool water balanced will be easier with bromine, as it has a lower pH level compared to chlorine. This means you’ll be spending less time testing your pool water, and also spending less money on additional chemicals.

The chloramines that are produced when chlorine stops being effective are non-existent when it comes to bromine, and the latter will continue to work even after it has sanitized the pool. However, chlorine does have more oxidizing power.

For high temperature water, bromine is the way to go. It can clean up to 58.8 degrees Celsius, while chlorine tops off at 32. Hot tubs use bromine for exactly this reason.

But when used in pool water, chlorine has a safety net in cyanuric acid. Cyanuric acid protects chlorine from rapid destruction by the sun’s UV rays. Bromine has no protection from this, and you’ll be constantly feeding it to your outdoor pool to keep the water clean.

Switching over from chlorine is easy enough, as bromine comes in tablet form and can be applied to the pool using a feeder. However, it’s recommended to purchase a separate feeder so that the bromine doesn’t come into contact with any traces of chlorine.

Pros:

  • Retains its cleaning efficiency
  • Less odour than chlorine
  • Lasts longer in hot water
  • Less harsh on your skin
  • Easier to keep pH level balanced 

Cons:

  • Less oxidizing power than chlorine
  • More expensive for outdoor pools
  • Highly destructive when exposed to the sun
  • More expensive for outdoor pools
  • Not as commonly used by pool professionals

2. Salt System

Contrary to popular belief, the water in saltwater pools isn’t on par with the chemical makeup of seawater, and they actually still use chlorine. These days, they’re actually the most popular type of chlorine pool.

But how they use chlorine is where things differ from a traditional pool.

Salt systems use a process known as electrolysis. 

First, salt is added to the pool water to create a saltwater solution. It’s then passed through a salt generator (aka salt cell) which uses electricity to break it down and convert it to hypochlorous acid (chlorine).

The level of salinity in these pools is similar to the salt level of human tears rather than ocean water, and the level of chlorine is much lower than if you were to use chlorine tablets or other traditional methods.

Aside from being a more gentle option for swimmers, salt systems can also save you money when it comes to all the chemicals that are usually needed to maintain pool water chemistry.

Pros:

  • Uses low amounts of chlorine
  • Less harsh for people to swim in
  • Less expensive for yearly chemical costs
  • Won’t fade bathing suits
  • Less maintenance required

Cons:

  • Can be expensive to install
  • Electricity bill will increase
  • Salt water may harm pool features and landscaping

3. Mineral System

Before salt systems were around, mineral systems or mineral purifiers were the main alternative to chlorine pools. 

Mineral systems add a blend of mineral compositions to the pool water – sodium chloride (aka salt), magnesium chloride, potassium chloride, and borates. 

Silver and copper ions are also included. These ions keep the water disinfected, but cannot remove organic matter. It’s for this reason that low levels of chlorine (50% less) must still be used with this system.

The minerals are contained in a cartridge and released into the pool. One of the downsides of this system is that these cartridges are only good for a few months, and need to be replaced multiple times a year.

But the addition of minerals has a lot of upsides, with many swimmers reporting the water to have a softer feel, leaving their skin and hair feeling silky and healthy, instead of the harshness that chlorine residue provides.

Pros:

  • Potential for highest quality of water
  • Non-corrosive and safe for concrete, metal, and clothing
  • Water will feel softer
  • Less wear and tear on equipment
  • Easy to maintain

Cons:

  • Still requires chlorine
  • Mineral cartridge needs replacement every few months
  • Oxidation stains can form due to increased copper levels
  • Black stains on plaster finishes can result from high silver levels

4. Ionizer

Using a pool ionizer is another way to reduce chlorine consumption. It’s actually very similar to a mineral system, but there are a few differences.

While mineral systems add salt, borates, magnesium chloride, and potassium chloride to the water, an ionizer system does not.

What they have in common is they both use copper and silver ions to disinfect the pool’s water. 

But the main difference is that the ionizer creates them on site, whereas the mineral system uses a pre-filled cartridge that contains eroded ions. 

The ionizer creates silver and copper ions in real time and can be used ad infinitum. The prefilled cartridge of a mineral system needs to be replaced every few months.

As with the mineral system, low levels of chlorine must still be used with an ionizer, but as you only have to purchase the ionizer once, it will be the cheaper alternative in the long run.

Pros:

  • Only have to buy ionator once
  • Softer-feeling water
  • Less chlorine consumption
  • Less wear and tear on pool equipment

Cons:

  • Chlorine still required
  • Monthly electricity bill may go up
  • May need metal sequestrant to control metals from oxidizing/staining

5. Biguanide

Biguanide is a sanitizing liquid, and aside from bromine it’s the only other candidate that can offer you a chlorine free pool.


It comes in a 3-step cleaning system under brand names like Baquacil and SoftSwim. There’s multiple components for these systems because they have to make up for the sanitizing and oxidizing power that chlorine can do on its own.

Biguanide on its own is a sanitizer, with these pool care systems including oxidizers (to remove organic matter), algae controllers, and even clarifiers that will keep your water crystal clear. 

Many pool owners who have made the switch claim they’ll never go back to using chlorine. But the price tag of using a biguanide cleaning system may be a deal breaker for some.

Pros:

  • Eliminates chlorine use and chloramines
  • Pool care systems make it easy to know which products to add
  • Gentle on skin, hair, and eyes
  • Zero metals 
  • Still works well at elevated temperatures

Cons:

  • Expensive compared to chlorine
  • Sanitizing effect may taper off over time
  • Cloudy water may occur from time to time

6. Ozone

You may have heard that ozone is a very dangerous gas for humans to be around, and that is actually true.

It’s for this reason that pool ozone generators are located far down the filtration chain, and away from the pool itself in a well-ventilated area.

Ozone generators work by creating ozone gas, and then injecting it into the water before it returns to the pool. Ozone gas is 100 times stronger as an oxidizer than chlorine is. 

So why does the pool still need chlorine? Because the pool water still needs to be constantly sanitized. Ozone acts more like a filter, and is never present in the pool water.

There’s two types of ozone generators: corona discharge or UV light (ultraviolet light). Both are viable options, and do the same job of breaking apart oxygen molecules to create ozone.

Pros:

  • Multiple options to choose from
  • Low levels of ozone make it safe for pools and swimmers
  • Reduces chlorine demand
  • Ozone quickly dissipates so it won’t be released in the pool

Cons:

  • Must always be well-contained
  • Pool still requires some level of chlorine
  • Only works with PVC or stainless steel pipes/plumbing
  • Can result in high electricity bill

7. Non-Chlorine Shock

Non-chlorine shock works on the same principle as a few of these options, in that it acts as an oxidizer and allows the chlorine to focus solely on sanitizing the water. It can’t work as a sole sanitation method.

Also known as MPS (potassium monopersulfate), non-chlorine shock oxidizes body oils and other organic matter in the water. While chlorine can oxidize and sanitize, you usually use up more of it this way. 

This 2-chemical approach will give the chlorine longer life, and it will be more efficient at the same time.

Adding non-chlorine shock is also a quick way to clear up a cloudy pool, as it oxidizes the pollutants that are causing this issue.

Pros:

  • Better chlorine efficiency
  • Clears up cloudy pools
  • Eliminates chloramines
  • Can regenerate used bromine

Cons:

  • Not a chlorine-free option
  • Less money spent on chlorine

Bonus Alternative: Mother Nature

Building your own natural swimming pool is a unique and often overlooked option when it comes to a chemical-free alternative.

Unlike the many sanitizers and oxidizers we’ve covered, a natural pool uses a natural and biological ecosystem to keep the water clean, such as aquatic plants and other life often found in natural bodies of water.

While the building and maintenance is actually quite affordable, you will need to ensure proper circulation and prevent the buildup of algae, especially in harsh seasons and warmer climates.

Pros:

  • Requires absolutely zero chlorine/chemicals
  • Relatively inexpensive to build
  • Cheaper to maintain

Cons:

  • Relies on constant water circulation
  • Hard to maintain during harsh seasons
  • Doesn’t “feel” as clean as a chemically-aided pool

Which Chlorine Alternative Is Right For You?

With multiple options for a chlorine-free swimming pool, the choice can be confusing.

Every situation is different, so you’ll have to carefully weigh the pros and cons of each chlorine alternative system.

Salt system pools are very popular, and the most common “non-chlorine” option, but their high installation cost and potential to damage pool equipment may make you think twice.

A mineral or ionator option seems to be more of what most people are looking for when it comes to chlorine alternatives. The smooth and silky feeling they offer is a big plus, as no one wants to come out of a pool feeling like they just bathed in harsh chemicals.

Meanwhile, you can’t really go wrong with the actual chlorine-free options: bromine and biguanide. 

Bromine works just as well as chlorine (and is especially great for hot tubs), and biguanide does an impeccable job as well. The only downside to these is their price tags.

Your Non-Chlorine Pool Awaits

The bottom line? When it comes to achieving a chlorine free pool, you have options. At the end of the day, that’s pretty much all we ask for, isn’t it?

By weighing the pros and cons of each, you’ll find out which one works best for your situation. And really, there’s no wrong choice when it comes to this pool matter, just different ones.

Categories: Pool Care, Pool Chemistry