A saltwater pool is a chlorine pool. The difference is that instead of you adding chlorine, a cell in the plumbing makes it continuously from salt dissolved in the water. Everything else about the chemistry is the same.
This surprises a lot of people. The water is sanitised by exactly the same chlorine, at exactly the same levels, tested with exactly the same kit. What changes is where it comes from and how steadily it arrives.
The salt level is around a tenth of seawater — noticeable on the tongue but nothing like the sea, and gentler on eyes and skin mainly because the chlorine level stays steady rather than spiking after each dose.
At a glance
| Characteristic | Typical |
|---|---|
| Sanitiser | Chlorine, generated on site from salt |
| Salt level | 2,800 to 3,800 ppm — about a tenth of seawater |
| Free chlorine target | 2 to 4 ppm, the same as any pool |
| Cell life | Several years, then replacement |
| pH tendency | Drifts upward continuously |
Advantages and limitations
What works well
- Chlorine arrives steadily rather than in spikes, so the water feels softer and is easier on eyes.
- No jugs of chlorine to buy, carry or store.
- Less day-to-day intervention through the season.
- Salt is not consumed, so it only needs topping up after water loss.
What to weigh up
- pH drifts up continuously and needs watching more closely, not less.
- The cell is a consumable and replacing it is a significant cost.
- Salt is corrosive to some stone, metal fittings and nearby fixtures.
- Cold water reduces output, so spring and autumn often need supplementing.
- A cell cannot raise chlorine quickly — for algae, adding liquid chlorine directly is faster.
Looking after one
- Test free chlorine and pH weekly — pH in particular, because it rises steadily.
- Check salt level monthly with a test kit, not only the panel reading; cells under-read as they age.
- Inspect the cell for scale every three months and clean it per the manufacturer’s instructions.
- Keep cyanuric acid in range — salt pools still need stabiliser outdoors.
- Turn the output down in spring and autumn, and up in high summer.
What it costs to own
A salt system adds to the up-front cost, whether fitted at build or retrofitted to an existing pool. It also adds a modest amount to the electricity bill, since the cell draws power whenever it is generating.
Against that, you stop buying chlorine. Whether it works out cheaper depends mostly on cell life against local chlorine prices — and cell replacement is the number that decides it, so it is worth asking what a replacement costs before committing.
Prices for pools vary enormously by region, access, ground conditions and specification, so no figure is quoted here. The Ownership Cost Calculator uses your own numbers instead of an average that would be wrong for most people.
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CalculateQuestions people ask
Is a saltwater pool chlorine-free?
No. It is a chlorine pool that generates its own chlorine from salt. The sanitiser in the water is the same chlorine as in any other pool, at the same levels.
Is it salty to swim in?
Slightly. At around 3,200 ppm it is roughly a tenth as salty as the sea — noticeable if you swallow some, but not like swimming in the ocean.
Why does my salt pool’s pH keep rising?
The generation process itself produces a high-pH by-product, so the drift is built in. Expect to add acid regularly, and consider keeping alkalinity toward 80 ppm to slow it.
Do salt pools still need cyanuric acid?
Outdoors, yes. Generated chlorine is destroyed by sunlight exactly like any other chlorine, so it needs the same protection.
Can I shock a salt pool?
Yes, and sometimes you should. The boost function works slowly; for algae, adding liquid chlorine directly is faster and easier to control.