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View In PDFA saltwater pool is the better choice if you'd rather not buy, store and add chlorine, because a salt cell makes it for you from mildly salty water. It isn't chlorine-free, and it won't stop red eyes on its own. You pay for the cell up front, have it checked and cleaned regularly and replace it when it wears out.
Both systems use chlorine
Whichever system your swimming pool runs on, chlorine is what kills the germs in the water. Pool equipment maker Pentair calls the idea of a chlorine-free saltwater pool a common mistake, because a saltwater pool is still a chlorinated pool. What changes is where the chlorine comes from.
In a saltwater pool, the water passes through a salt cell fitted into the pipework by the pump and filter. The maker explains that the cell uses an electrical charge to turn dissolved salt into chlorine, a process called electrolysis. Once that chlorine has done its job, it turns back into salt and the cell uses it again, according to the maker's older IC15 manual.
The water is only mildly salty. The maker calls the salt level its cells need relatively low compared with sea water, and its current manual puts the ideal at 3,600 parts per million, or ppm, the unit pool water tests use. That's about 3.6 grams of salt in each litre.
In a chlorine pool, you add the chlorine yourself or a device does it for you. This manufacturer also lists floating dispensers, tablet feeders and electronically controlled injection systems, and says the floating and tablet types dose inaccurately.
The cell makes chlorine but doesn't test it
A salt cell only makes chlorine. The maker's current manual says its cells are not intended to monitor or maintain proper free chlorine levels, so someone still has to test the water for free chlorine, the chlorine that's still available to kill germs.
The control panel is easy to misread. On the maker's current cells, the display shows the output percentage and the latest salt reading, and neither one is the chlorine level. The output percentage is the share of the pump's running time the cell spends making chlorine, so at 80% it rests for a fifth of that time.
The cell also works only while the pump runs and pushes enough water through it. In the maker's current range, the cell won't make chlorine below 94.6 litres a minute, so if a variable-speed pump is turned down below that flow, chlorine production stops. Our guide to variable-speed pool pumps explains how pump settings are matched to equipment like this.
Setup Cost Differences
A salt system adds equipment that a pool dosed by hand doesn't need. In Pentair's current range, that's the cell and a power centre or power pack that turns mains power into the low-voltage current the cell runs on. Add the wiring, a first load of salt and the set-up.
The maker says this equipment should only be installed and serviced by a qualified professional. It has to be wired so the cell only gets power while the pump runs, and the maker warns that chlorine gas can build up if the wiring is wrong.
A chlorine pool can start with less. If you dose by hand, you need a test kit, the chlorine and a safe place to keep it. An automatic feeder or dosing system adds its own equipment and set-up, and our guide to planning the pool equipment area treats chemical storage as a decision of its own.
Is a saltwater pool more expensive?
To set up, yes, compared with dosing by hand, because you're buying the cell and its controls. After that, you stop buying chlorine apart from the odd shock dose, but take on the cell's upkeep and, in time, its replacement.
Building a new pool or converting one
On a new pool, the salt cell doesn't start on day one. The maker says the pool must be full for at least a month, with the salt level stable, before its cell runs, and a newly plastered pool needs at least a month to cure before any salt goes in. Until then, the water is treated with chlorine you add, starting with a shock dose (a strong one-off dose of chlorine) from a pool supplier.
Converting an existing pool needs three checks first. The pump has to push enough water through the cell, there has to be space and power for the cell near the other equipment, and everything metal or stone the water touches has to cope with salt.
Space matters more than it sounds in a small garden. The maker's instructions put its cells at least 1.5 m from the inside wall of the pool, to reduce the risk of electric shock, and at least 0.9 m from a heater outlet.
Running Costs and Maintenance
Both pools need regular water tests, because chlorine gets used up whichever way it arrives. Our swimming pool maintenance guide covers the testing, cleaning and equipment care that come with any pool.
How to look after a saltwater pool
Pentair's routine for its current salt cells is a weekly test of pH, alkalinity and chlorine, a monthly salt and water-balance check, and a look inside the cell at least every two months. The pH tells you how acidic the water is, and alkalinity keeps the pH steady. Here's who should do each part.
| How often | What's checked | Who does it |
|---|---|---|
| Every week | pH (ideal 7.4 to 7.6), total alkalinity (80 to 120 ppm) and free chlorine (2 to 4 ppm), with the cell's output turned up or down to hold the chlorine | You or your pool service, with a reliable test kit |
| Every month | Salt (ideal 3,600 ppm, topped up only after a test), plus stabiliser (which protects chlorine from sunlight), metals and the other water-balance readings a pool shop can test from a sample | You or your pool service, or a water sample sent for testing |
| At least every two months | The cell is taken out and checked for scale and debris, and acid-cleaned if it's heavily scaled | A pool technician, because it means switching off power at the main breaker, releasing filter pressure and handling acid |
The cell check every two months isn't a DIY job. The maker's steps start with switching off power to the pump, controls and cell at the main breaker and releasing the filter's pressure, and its acid wash uses muriatic acid, a strong acid that it warns can be dangerous. Your part between visits is to look at the control panel and note any warning, without opening the equipment.
What a chlorine pool asks of you instead
With a chlorine pool, the weekly water tests stay the same, and the chlorine becomes something you buy, carry home, store and add. That's the job a salt cell takes off your hands, and the maker sells its current cells as an alternative to buying, handling, storing, and carrying chlorine.
If your pool service already brings and adds the chlorine, the handling a salt cell saves is mostly theirs, not yours. If you do it yourself, plan where the chlorine is kept and who adds it when you're away. Follow the label every time, because the maker's manual warns that even proper use of the recommended chemicals can be hazardous.
What you pay for with each
| Cost | Saltwater pool | Chlorine pool |
|---|---|---|
| Chlorine | Made by the cell, plus a shock dose at start-up and as needed, which the maker recommends | Bought, stored and added all year |
| Salt | Topped up when the monthly test shows it's low | None |
| pH and balance chemicals | Acid to bring pH down, plus stabiliser and others as tests show | Also needed, as tests show |
| Electricity | The cell's own use on top of the pump, 63 to 206 watts across the maker's current range | An automatic dosing system's own use, if you have one |
| Equipment upkeep | Cell checks and cleaning, and a new cell when the old one wears out | Servicing and parts for a feeder or dosing system, if you have one |
The cell is the cost to plan for, because it wears out. The maker designed its older IntelliChlor IC15 cell for approximately 10,000 hours before replacement, which it puts at roughly five years of average use. The maker's current cells keep a count of the hours they've spent making chlorine, and that count is the number to check when anyone suggests a replacement.
To compare the two for your pool, ask for the price of a replacement cell for the model you're offered and how long its maker expects it to last. Set that against what you spend on chlorine now. Our guide to monthly pool maintenance costs shows how to build the rest of the budget from your service quote and utility bills.
How They Feel to Swim In
A saltwater pool isn't healthier just because it's salt, since the same chlorine disinfects the water in both kinds of pool. Whether it stings your eyes or skin comes down to how the water is kept and how clean swimmers are when they get in.
A strong "chlorine" smell is probably chloramines, and they can cause red, itchy eyes, skin irritation and rashes. The US Centers for Disease Control and Prevention (CDC) explains that chloramines form when chlorine combines with sweat, dirt and pee from swimmers.
That happens in any chlorinated pool, salt or not. Chloramines also leave less chlorine available to kill germs, so a strong chlorine smell probably means less protection, not more.
What helps is the same for both. Keep the chlorine and pH in range, and have everyone rinse off before getting in, because the CDC says a one-minute shower can remove most of the dirt on your body.
If anyone gets red eyes, a rash or a cough after swimming, or the pool smells strongly of chemicals, stop using it until the water has been tested. If symptoms don't settle, see a doctor.
Tile, Coping, and Equipment Wear
The catch with salt is what it can do to materials. Pentair calls salt an inherently corrosive material and warns that metal parts and certain pool surfaces are particularly likely to corrode or deteriorate.
The maker also doesn't promise that using its cell properly will prevent corrosion, and it tells you to get a pool professional's advice on the materials. So before you choose salt, have the installer go round the pool with you and list everything metal or stone that the water and splashes reach.
- Ladders, grab rails and the fittings that hold them
- Underwater lights and their surrounds
- The pump, filter and any heater or heat pump
- Cover mechanisms and any metal edging
- Stone coping, paving and wall finishes around the pool
For each one, ask whether it suits salt water and how it should be looked after. Where something doesn't, decide before the salt goes in, because lowering the salt later means draining some water and refilling with fresh, which is what the maker advises for high salt levels.
Keep the salt in range, too. The maker says salt above 6,000 ppm can speed up corrosion of equipment in and around the pool and discolour its surfaces, and that salt with anti-caking agents can discolour fittings and finishes.
Corrosion isn't only a salt problem. The maker's older IC15 manual warns that free chlorine above 4.0 ppm may cause corrosion of metal components, and its current manual says water that's out of balance can damage equipment, whichever way the chlorine gets in. Our guide to pool finishes compares the tiles and surfaces themselves.
Which Is Right for Your Pool?
Choose salt if you'd rather not buy, store and add chlorine, you'll keep up the cell checks and budget for a new cell in time, and the fittings around the pool suit salt water. Stay with chlorine if there's metal or stone around the pool that won't take salt, your current dosing works well, or your pool service already brings and adds the chlorine.
On a new pool, we recommend deciding before the finishes are chosen. The fittings, the coping and the space for the equipment can then be picked for salt from the start, instead of checked afterwards.
Our swimming pool buying guide puts the water treatment alongside the other decisions in a new pool, from its size and use to the equipment schedule and chemical storage.
If you're planning a new pool, tell us in your message which system you're leaning towards and send any plans you have. We'll do a free site assessment to measure up and check where the pump, filter and any salt cell would go, and your fixed-price quote follows within 3 to 5 working days of that visit, never from photos. Our specialist builds the pool, and we supervise the work through to handover.
Common questions
Can a plunge pool be saltwater?
Yes, a built-in one can. Pentair makes its cells for permanently installed pools, not storable or steel pools, and a spa or hot tub needs a cell marked for that use. Its smallest current cell is rated for pools of up to 56,800 litres, and the output can be turned down for a smaller pool. To get your pool's volume in litres, multiply length by width by average depth in metres, then by 1,000. Our comparison of plunge pools and lap pools covers the size and space side.
Do you ever add chlorine to a saltwater pool?
Sometimes. Pentair recommends a shock dose from a pool supplier when a new pool starts up, then as needed to keep the chlorine in range. Leave the choice of product to your pool technician. The maker's manual warns that using trichlor or dichlor with a salt chlorine generator may result in death or personal injury. Check any product label for trichlor or dichlor, or their full names, trichloroisocyanuric acid and dichloroisocyanuric acid.
What happens if a saltwater pool runs low on salt?
On Pentair's current cells, an ADD SALT warning comes up below 3,000 ppm, and the cell shuts off below 2,600 ppm, so it stops making chlorine. Have the chlorine tested before anyone swims, and add salt only after a salt test, because the maker says most pools already contain some salt.
Does a salt cell warning mean the cell needs replacing?
Not always. Pentair lists a low output setting, too little run time, rain, heavy use, fertiliser and dirty or scaled blades among the causes of low chlorine, and on its current cells the electronics and sensors can be replaced on their own. Its sign of worn-out blades is a Check Cell warning that stays on after the cell has been cleaned, so have a technician find the cause before you pay for a new cell.
What destroys chlorine in a pool?
Sunlight and the swimmers themselves both use it up. Pentair's IC15 manual says the sun's UV destroys 90% of unstabilised chlorine within two hours, which is why an outdoor pool under Singapore's sun needs a stabiliser. Sweat, dirt and pee use up chlorine as they form chloramines. That happens in saltwater and chlorine pools alike.
Swimming Pools across Singapore
Need help with your project?
Tell us what you need on WhatsApp and send a few photos. We'll arrange a free site assessment, then give you a fixed-price quote within 3 to 5 working days.