Salt Chlorinator vs Traditional Chlorine: Which is Better?

2024-12-15

"Should we convert to salt?" is one of the questions we hear most. Both systems sanitise a pool with chlorine — a salt pool simply makes its own. The right answer depends on your budget, how hands-on you want to be, and a local factor that matters more than most brochures admit: Gauteng's hard water. This guide explains how each system works, the real advantages and drawbacks of both, and how to decide.

Does a salt pool use chlorine?

Yes. A salt chlorinator is a chlorine generator. Salt (sodium chloride) is dissolved in the pool water at a level far below that of the sea. As the water passes through the chlorinator's electrolytic cell, a low-voltage current converts some of the chloride into chlorine, which sanitises the pool exactly as added chlorine does. When the chlorine has done its work it reverts to salt, and the cycle repeats. Salt is lost only through splash-out, backwashing and overflow after rain, so it is topped up occasionally rather than added every week.

How does traditional chlorine dosing work?

With traditional dosing, you add the chlorine yourself, in one of these common forms:

• Granular calcium hypochlorite — the type sold under brands such as HTH. Fast-acting, widely available and good for shock dosing, but it adds calcium to the water with every dose.
• Stabilised chlorine tablets (trichlor) in a floater or feeder. Slow and convenient, but they lower the pH and steadily build up stabiliser in the water.
• Liquid chlorine (sodium hypochlorite). It adds no calcium or stabiliser, but it is bulky to carry and loses strength in storage.

What are the advantages of a salt chlorinator?

• Convenience. Once it is set up and balanced, the pool makes chlorine every time the pump runs. No weekly buying, carrying and storing of granular chlorine.
• Steadier chlorine. Production follows pump run-time, so there are fewer peaks and troughs than with manual dosing.
• Less chemical handling and storage at home — a real safety benefit with children around.
• Softer-feeling water. Many swimmers find a well-run salt pool gentler on the eyes and skin, partly because steady chlorine means fewer of the chloramines that cause the "chlorine smell".

What are the disadvantages of a salt chlorinator?

• Upfront cost. The chlorinator, the cell and the first load of salt cost far more at the start than a bucket of chlorine.
• The cell wears out. Cells have a working life and eventually need replacing, and they are not cheap.
• Scale in hard water. This is the big Gauteng issue. Hard municipal water deposits calcium on the cell plates, and a scaled cell produces less and less chlorine until the pool goes green — often while the control box still shows it running. The cell needs regular inspection and cleaning.
• pH drifts up. Salt chlorination pushes the pH upward, so you add acid more often. Leave the pH high and the scaling gets worse.
• Corrosion. Salt water is harder on some metals, natural stone coping and nearby plants. Check that your ladder, fittings, light, heater and cleaner are suitable for salt water.
• It depends on the pump. No pump hours, no chlorine. Load-shedding that cuts pump time also cuts chlorine production.

What are the advantages of traditional chlorine?

• Low upfront cost, and nothing to install.
• Simple and familiar. Easy to understand, and easy to shock when the pool needs it.
• No cell to scale or replace, and no salt to corrode fittings.
• Flexibility. You can raise the chlorine quickly after a storm, a party or a heat wave.

What are the disadvantages of traditional chlorine?

• Regular handling. Someone has to buy, carry, store and dose chemicals every week.
• Peaks and troughs. Levels run high after a dose and low before the next one, which is when algae gets its start.
• Side effects. Granular chlorine adds calcium, which on top of hard water feeds scale. Tablets push stabiliser up until the chlorine becomes sluggish and part of the water has to be replaced.
• Storage. Granular chlorine is a strong oxidiser, and it must be kept dry, locked away, and well apart from acid and from children.

Which costs more over time?

It depends on your pool size, how many hours the pump runs, how much chlorine your pool uses in summer, and how long a cell lasts in your water. A salt system costs more upfront and less in chemicals afterwards, with a cell replacement somewhere down the line; manual chlorine costs little upfront and more every month. Rather than trust a generic comparison, work it out for your own pool with current prices — the product pages in our online pool shop list salt chlorinators, replacement cells and chemicals.

How do I look after a salt chlorinator in Centurion or Pretoria?

• Keep the pH at 7.2–7.6 and check it every week; salt pools push it up.
• Look at the cell every few months, and clean it when you see white scale on the plates. Hard-water areas need it more often.
• Keep the salt within the range on your chlorinator's label. Too little makes the cell work harder; too much is wasted money.
• Turn the output up in summer and down in winter, rather than leaving one setting all year.
• Still shock the pool after heavy use or a big storm; the cell cannot always catch up on its own.

A chlorinator service at R1,299 covers cleaning the cell and inspecting the plates, the flow switch, the connections and the control box readings, and we check the salt level at the same time. Our pool repairs page covers chlorinator faults in more detail.

How much salt does a salt pool need?

Follow the range printed on your chlorinator or in its manual, because different makes are designed for different salt levels. Test the salt with a salt test strip or a meter rather than relying on the control box alone, and add salt only when a test says it is low. Use pool-grade salt, spread it across the shallow end with the pump running, and brush it until it has dissolved so it does not lie on the floor. The chlorinator does not use salt up; it is lost with the water that leaves the pool, so test again after heavy rain has overflowed the pool or after a long backwash. Too little salt makes the cell work harder and shortens its life; too much wastes money and can set off a high-salt warning.

So which is better?

Choose salt if you want convenience, steadier chlorine and less handling of chemicals, can afford the upfront cost, and are willing to keep an eye on the pH and the cell. Stay with traditional chlorine if you want the lowest upfront cost, like to dose exactly when you choose, or have fittings or stone that do not suit salt. Either way, the basics do not change: the pH in range, enough pump hours, and a clean filter.

If you would rather not manage either system yourself, a weekly pool maintenance plan looks after salt and chlorine pools alike. We look after pools in Pretoria East, Centurion, Pretoria and Midrand.

Frequently asked questions

Why is my salt pool green?

Usually a scaled cell, low salt, a pH left high or too few pump hours. Clean the cell, check the salt and the pH, and shock the pool to catch up. Read why your pool turns green for the full recovery.

Can an existing pool be converted to salt?

Most can. Check that the surface, the fittings and any heater are suitable for salt water, and that the chlorinator is sized for your pool's volume.

Does a salt pool taste salty?

Slightly, but the salt level is far lower than seawater.

Do I still need to add acid to a salt pool?

Yes. Salt chlorination pushes the pH up, so pH correction is a regular job.

Talk to us

WhatsApp or call Crystal Reef on 081 577 5051 with a photo of your chlorinator's control box and cell, or email sales@crystalreef.co.za.