Saltwater Pools. The Quiet Revolution in Polypropylene Pool Care

How salt electrolysis works

The principle is simple and surprisingly elegant. A small amount of salt is added to the water — typically 3–5 kg per 1000 litres, a concentration of 0.3–0.5%. The water then flows through an electrolyser, a device in which low-voltage current breaks ordinary salt (NaCl) down into its components. One of them is chlorine — the same chlorine that disinfects water in traditional pools, except here it is produced continuously, automatically, right inside the pool's circulation loop.

Fun fact: the process mimics what happens naturally in the oceans. UV radiation in seawater produces small amounts of chlorine that help maintain microbiological balance. An electrolyser does exactly the same thing, only under the controlled conditions of your own garden. An even better fact: the salt concentration in such a pool is close to the natural salt level in human tears and physiological saline. That's why the water doesn't sting your eyes or dry your skin the way conventional chlorinated water does.

Why polypropylene is the material made for saltwater

Here's where it gets interesting. Salt is aggressive toward many materials — it corrodes metals, attacks steel elements, reacts with certain coatings. In reinforced-concrete pools or pools with extensive metal hardware, salt electrolysis requires additional protection and expensive modifications.

Polypropylene stands out here. It is completely chemically inert — it doesn't react with salt, doesn't corrode, doesn't lose colour or mechanical properties. It remains fully stable across a temperature range of -30 to +90°C, and its smooth, non-porous surface absorbs nothing and collects no deposits. A polypropylene pool with saltwater can run for decades without any risk of shell degradation.

In practice: combining PP technology with salt electrolysis gives you a setup that requires minimal intervention after installation. You top up the salt once per season, the electrolyser runs automatically, and the shell — simply doesn't wear out.

Electrolysis vs traditional chlorination

Classic chlorination requires regular tablet dosing, constant monitoring and coping with the side effects: the characteristic smell, eye and skin irritation, faded swimwear. A salt electrolysis pool eliminates almost all of that. Chloramine levels — the compounds responsible for the typical "pool smell" — are significantly lower, because the chlorine is generated in a more reactive form and returns to salt faster. Seasonal running costs are often reduced by tens of percent. And there's no need to store chemicals in the garage.

The only substantial investment is the electrolyser itself — a one-time cost that typically pays back within 2–4 seasons of regular use.

Health benefits — what the science says

Swimming in saltwater means inhaling a microclimate similar to that found in salt inhalation facilities. The fine mist above the water surface has a cleansing effect on the respiratory tract — particularly valuable for allergy sufferers and people with sinus issues. Skin behaves differently than in chlorinated water: instead of drying out and redness, it comes out smoother and better hydrated. Salt gently exfoliates dead skin cells and stimulates microcirculation. For the eyes, saltwater is literally more natural — our tears are a saline solution of very similar concentration.

What you should know before deciding

Salt levels should be checked every two weeks with a test strip — a matter of seconds. Water pH still needs regulating; electrolysis doesn't replace that step. The system requires dedicated pool salt (anti-caking-free and iodine-free), compliant with EN 16401. The technology works well for private pools up to 120 m³ of capacity.

The bottom line

A polypropylene pool with salt electrolysis combines the durability of a chemically resistant material, lower running costs, superior swimming comfort and real health benefits. At PP-Pools we design shells specifically tailored to this technology. If you're planning to build a pool or considering switching your existing disinfection system — get in touch. We'll show you concrete solutions and installations that have been running for our clients for years.