Saltwater or chlorine pool: which should you choose?

The framing is wrong, and it matters

“Saltwater versus chlorine” sets up a choice that does not exist. Both pools are chlorinated pools.

A salt chlorinator works by electrolysis. Water carrying dissolved salt passes over an electrode cell, the current splits the salt, and chlorine is produced in the water. When it has done its sanitising work it reverts to salt, and the cycle repeats. The salt is not the sanitiser. It is the feedstock.

Which is why several of the things people believe about salt pools do not follow. A salt pool is not chlorine-free. It will not suit someone who reacts to chlorine, because there is chlorine in it. And it is not automatically gentler — what tends to be gentler is the steadiness, because a machine generating continuously produces fewer spikes than a person dosing on Saturdays. You can achieve the same steadiness manually with discipline, and plenty of people do.

The concentration is also lower than the word “saltwater” suggests. Australian chlorinators are typically run somewhere between roughly 2,700ppm and 6,000ppm depending on the unit — noticeably less salty than seawater, which is why a salt pool tastes faintly of it rather than like the ocean.

So the real question is not which sanitiser. It is whether you would rather own a machine or handle chemicals. That is a much easier question to answer honestly about yourself.

The decision rule: amortise the cell

Most comparisons stop at “salt costs more upfront and less to run”, which is true and useless, because it omits the one recurring cost that decides the arithmetic.

The cell is a consumable. The electrode plates degrade in use and are replaced every three to five years. It is not a fault and not a warranty matter; it is how the technology works, in the same way tyres are how a car works.

So here is the rule, and it takes one line:

Divide the replacement cell price by the years it lasts, add that to your annual chemical and power cost, and compare that total. Anything that ignores the cell is comparing an incomplete number.

Worked through with published Australian figures:

• Annual chemical saving from salt: about $300–$350.
• Cell replacement every 3–5 years, advertised at roughly $400–$900, with aftermarket cells around $360–$499 and some original-equipment parts at $830–$1,099.
• Amortised, that is roughly $80 to $300 a year depending on which cell and how long it lasts.

Which is the entire finding: the case for salt is strong on a cheap cell that lasts five years and close to neutral on an expensive cell that lasts three. The variable that decides it is not the pool. It is the replacement price of the cell your chlorinator takes.

These figures are advertised prices collected from Australian suppliers and industry guides — nobody regulates or independently surveys them, and we have not adjusted them. Use the method with your own quotes rather than treating the numbers as a benchmark.

The question to ask before you buy the chlorinator

Follow the rule to its conclusion and you get a question that is almost never asked at the point of sale, and that costs nothing to ask:

“What does a replacement cell for this unit cost today, and is there an aftermarket equivalent?”

You are buying a machine whose consumable you will purchase three or four times over the pool's life. A $170 difference in the chlorinator is irrelevant next to a $500 difference in the cell, repeated every four years.

Two things to listen for in the answer:

• Whether the cell is proprietary. Some units take only the manufacturer's own cell; others have compatible aftermarket options. That is the single largest driver of the spread above.
• Whether the salt range is narrow. Published Australian targets vary widely by unit — some run near 3,200ppm, others need 5,000–6,000ppm. A unit with a narrow window is less forgiving of rain dilution and backwashing. Stay inside your manufacturer's stated range rather than any general figure, including the ones above.

And one honest caveat on the sanitiser choice itself: salt is harder on some materials. Natural stone coping, certain renders, metal fixtures, light surrounds and some fasteners all live in a saltier environment than they otherwise would. It is manageable with the right material choices, and it is a reason to raise the topic with your builder at design stage rather than after the travertine is laid.

Who each option is genuinely wrong for

Salt is the wrong choice if:

• the pool is small, or a plunge pool used seasonally — the chemical saving scales with water volume, and on a small pool it may never repay the equipment;
• you expect to sell within a few years, since you pay the install and someone else gets the savings;
• the design leans heavily on natural stone or metal you would rather not expose to salt;
• upfront budget is the binding constraint. It usually is, and that is a legitimate reason.

Manual chlorination is the wrong choice if:

• you know you will not dose consistently — and be honest, because an under-dosed pool is a far worse outcome than either system done properly;
• you are holding the property long term, where the annual saving compounds;
• you dislike storing and handling pool chemicals, which is a perfectly good reason on its own;
• the pool is large, where the chemical saving is largest.

A third path exists and is worth knowing about: mineral systems, typically magnesium-based, which also generate chlorine but from a different salt blend. They are marketed on feel and on lower corrosivity, they cost more to run, and several of the strongest claims made for them are vendor-sourced rather than independently established.

Whichever way you go, this is a decision made at design stage and expensive to reverse. If you are still gathering prices, ask each builder to quote the chlorinator as a named model rather than as “salt system”, then apply the rule above — compare pool quotes on that basis, and see what a pool costs to run per year for the rest of the running-cost picture.

Common questions

Sources

• Pool Advisor Australia — Best salt water pool chlorinators
• ProductReview.com.au — Chlorinators, Australian consumer reviews
• Pool Calculator Australia — Pool salt calculator and salt levels

General information only, current at 2026-09-18. Pool rules differ by state and by council, and penalty amounts are updated regularly. Confirm your own obligations with your council or a registered inspector before acting.