Saltwater Pool Maintenance Guide
A saltwater pool is still a chlorine pool. The difference is where the chlorine comes from: instead of pouring it in, a salt chlorine generator (SWG, or “salt cell”) makes it from dissolved salt. That removes the daily chore of dosing chlorine, but it adds a few habits of its own. This guide covers what the system needs and the routine that keeps it running smoothly.
How a salt chlorine generator works
The cell sits in the return plumbing. As water flows through it, a low-voltage current passes between coated titanium plates and turns chloride from the dissolved salt into chlorine. The chlorine sanitizes the pool, breaks down, and turns back into salt, so the salt is reused over and over.
Two side effects matter for maintenance. First, the process makes hydrogen gas and creates a slightly alkaline environment at the plates, which pushes pH up. Second, the plates gradually collect calcium scale, especially when pH and calcium are high.
Target levels for a salt pool
| Parameter | Typical target | Why |
|---|---|---|
| Salt | 3,000–3,200 ppm (check your cell) | The cell needs salt within its range to make chlorine |
| Free chlorine | About 5–7.5% of CYA or more | Same rule as any chlorinated pool |
| CYA (stabilizer) | 60–80 ppm | Protects the steady chlorine output from sunlight |
| pH | 7.4–7.6 | Rises steadily because of the cell |
| Total alkalinity | 60–80 ppm | Lower TA slows the pH rise |
| Calcium hardness | Per your surface | Too high scales the cell |
The salt range printed in your cell’s manual (and often on the control panel) always wins over this table.
Adding salt
A newly filled pool needs a lot of salt, and after that you only top up what leaves with splash-out, backwashing and rain overflow. Salt does not evaporate.
| Pool | New fill → 3,200 ppm | Top up 2,800 → 3,200 ppm |
|---|---|---|
| 10,000 gal | 267 lb (7 bags) | 33 lb (1 bags) |
| 15,000 gal | 401 lb (11 bags) | 50 lb (2 bags) |
| 20,000 gal | 534 lb (14 bags) | 67 lb (2 bags) |
| 25,000 gal | 668 lb (17 bags) | 83 lb (3 bags) |
| 30,000 gal | 801 lb (21 bags) | 100 lb (3 bags) |
Bags of 40 lb, rounded up. Computed with the pool salt calculator's formula.
Use the pool salt calculator for your exact volume and current level. To add it: turn the cell off, spread the salt around the shallow end, brush any on the floor toward the main drain, run the pump for 24 hours, retest, then turn the cell back on. Use pool salt or plain sodium chloride of high purity without anti-caking agents or iodine.
Weekly routine
- Test free chlorine and pH. Adjust the cell’s output percentage to keep chlorine at the level your CYA calls for.
- Lower pH with acid as needed; a salt pool usually needs a small acid dose every week or so. The pH calculator gives the amount.
- Empty skimmer and pump baskets and check filter pressure.
Monthly routine
- Test salt with strips or a meter. The cell’s own reading can drift, so confirm it separately.
- Test CYA, alkalinity and calcium. Adjust stabilizer with the CYA calculator.
- Look inside the cell if it is the clear type, or check for a “clean cell” warning. White flakes between the plates are calcium scale.
Cleaning the salt cell
Many cells reverse polarity automatically to shed scale, but most still need an occasional cleaning. Follow your manufacturer’s instructions; typically you soak the cell in a diluted acid solution until the fizzing stops, then rinse. Always add acid to water when diluting, work outdoors, and wear gloves and eye protection. Scraping the plates with metal tools can damage the coating.
Keeping pH at 7.4–7.6, alkalinity at the low end and calcium in range does more to prevent scale than any cleaning schedule.
Seasonal tasks
- Opening: balance the water, add salt to the target before turning the cell on, and boost chlorine with liquid chlorine while the cell catches up.
- Cold water: most cells reduce output or shut off when the water gets cold. Use liquid chlorine if you keep the pool open.
- Closing: follow the cell manufacturer’s winterizing steps, which usually include removing or bypassing the cell.
Troubleshooting
- Chlorine stays low even at 100% output: check salt level, clean the cell, check CYA (too low means sunlight wins), and make sure the pump runs long enough each day. You can supplement with the chlorine calculator while you fix the cause.
- pH climbs every few days: lower total alkalinity toward 60–80 ppm and reduce aeration from water features.
- “Low salt” warning but the test says otherwise: clean the cell and check the flow sensor before adding more salt.
- White deposits on tile or in the cell: check the overall balance with the LSI calculator and bring pH and calcium down.
Is a salt pool cheaper to run?
You spend less on chlorine, but the cell uses electricity and eventually needs replacing, and you will buy acid regularly. For most owners the running costs end up similar; the real benefit is convenience and steadier chlorine levels.