How much baking soda for a 15,000 litre pool?
Sodium bicarbonate is the one product that raises total alkalinity without moving pH much. Here is the amount for a 15,000 litre pool, by how far the reading needs to move.
To raise total alkalinity by 30 ppm in 15,000 litres
↳ Nudges pH up slightly.
Change the volume or the readings and it recalculates.
Dose table for 15,000 litres
| Alkalinity rise (ppm) | Sodium bicarbonate |
|---|---|
| 10 | 252 g |
| 20 | 504 g |
| 30 | 756 g |
| 40 | 1.01 kg |
| 50 | 1.26 kg |
| 60 | 1.51 kg |
| 70 | 1.76 kg |
| 80 | 2.02 kg |
| 90 | 2.27 kg |
| 100 | 2.52 kg |
Fix alkalinity before you chase pH
Alkalinity is the buffer that stops pH swinging, so it is worth fixing before you chase a pH reading. Baking soda raises it and nudges pH up slightly on the way. If both readings are low, raise alkalinity first and test again: pH often comes up on its own.
Dosing a 15,000 litre pool
15,000 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 it slowly over the deep end with the pump running.
- Give it a full turnover and re-test before a second dose. Overshooting alkalinity is slow and tedious to undo.
Frequently asked questions
How much baking soda raises alkalinity in a 15,000 litre pool?
756 g raises total alkalinity by 30 ppm in 15,000 litres, for example from 60 to 90 ppm. The dose is linear, so a 10 ppm rise takes a third of that.
Will baking soda raise my pH as well?
A little. Sodium bicarbonate is close to neutral, so even a large alkalinity correction moves pH by a couple of tenths at most. Soda ash is the product for when pH itself is the problem.
What should total alkalinity be?
60 to 120 ppm suits most pools. Salt pools and plaster do better nearer the low end, because both push pH up over time.
How this is worked out
Every number here comes from the same engine as the DoseMyPool app and the calculator above, run at 15,000 litres. Amounts are estimates: product strengths vary, so follow the label on the bottle you own. See the full method
Other chemicals for 15,000 litres
Other pool volumes
Get exact doses, saved and on schedule
DoseMyPool remembers your pool, gives the safe order to add things, and reminds you to test. Free on the App Store.
Coming soon to the App Store