How much salt for a 40,000 litre pool?
Salt for a 40,000 litre pool, from a fresh fill or from wherever your reading sits now. 3,200 ppm is the usual target, but the manual for your cell wins.
To take a fresh fill to 3,200 ppm in 40,000 litres
↳ Run the pump 24h to dissolve before trusting the generator’s reading.
Change the volume or the readings and it recalculates.
Dose table for 40,000 litres
| Current salt (ppm) | Salt to add |
|---|---|
| 0 | 129.29 kg |
| 500 | 109.09 kg |
| 1,000 | 88.89 kg |
| 1,500 | 68.69 kg |
| 2,000 | 48.48 kg |
| 2,500 | 28.28 kg |
| 3,000 | 8.08 kg |
Salt is never used up
A salt cell makes chlorine out of salt and then the chlorine turns back into salt, so the level only falls through splash-out, backwashing and rain overflow. Nothing consumes it. That makes overshooting the expensive mistake, because the only way back down is draining and refilling.
Dosing a 40,000 litre pool
40,000 litres is a typical family pool, where one turnover of the water takes roughly six to eight hours. Add the full dose with the pump running and give it a turnover before testing, or you are reading the water around the chemical rather than the pool.
Safety
- Broadcast salt over the deep end and brush it around, then run the pump for 24 hours before trusting a reading.
- Leave the cell switched off until it has dissolved.
Frequently asked questions
How much salt does a 40,000 litre pool need?
129.29 kg takes a 40,000 litre pool from fresh water to 3,200 ppm. If there is already salt in it you only add the difference, which the table above works out.
What salt level should I run?
Most cells want 2,700 to 3,400 ppm and print the number on the unit. Running low makes the cell work harder and shortens its life; running high can corrode fittings.
What kind of salt?
Plain sodium chloride with no anti-caking agent, no iodine and no yellow prussiate of soda. Bags sold for pools and for water softeners both work.
How this is worked out
Every number here comes from the same engine as the DoseMyPool app and the calculator above, run at 40,000 litres. Amounts are estimates: product strengths vary, so follow the label on the bottle you own. See the full method
Other chemicals for 40,000 litres
Other pool volumes
Get exact doses, saved and on schedule
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