How to raise pH in a pool The short answer To raise pH in a pool, add soda ash (sold as “pH Up” or “pH Increaser”) with the pump running: dissolve it in a bucket of pool water and pour it around the edge. About 15 oz takes 10,000 gallons from pH 7.2 to 7.5 when alkalinity is 80 ppm — the calculator below works out your pool. If alkalinity is also low, raise it first with baking soda.
How much pH Up your pool needs pH now
How acidic the water is. Right, chlorine works and eyes do not sting; wrong, it damages the pool.
pH you want
Good range: 7.2–7.8.
Alkalinity (if you know it)
It decides how far a dose moves pH. Empty = a typical 80.
Stabilizer (if you know it)
Stabilizer buffers pH too. Empty = a typical 30.
Using pH up.
Type the size and your pH reading.
Step by step Test pH and alkalinity. The good range for a pool is pH 7.2–7.8; aim for about 7.5.
If alkalinity is under 60 ppm, raise it first with baking soda — it lifts pH a little too, and it stops pH from sliding back down.
Work out the dose for your pool with the calculator on this page.
Dissolve the soda ash in a bucket of pool water and pour it slowly in front of a return jet, with the pump running. A big dose goes in parts.
Wait a few hours, test again, and add the next part only if pH is still low.
The product label always wins — if it says something different, follow the label.
Why it happens pH falls when acid gets into the water: rain, trichlor chlorine tablets (they are acidic), and the acid you added to lower pH or alkalinity.
Aeration — fountains, waterfalls, jets pointed up — raises pH without adding anything, and is the gentle way to nudge it up.
Questions Can I use baking soda to raise pH? Baking soda mostly raises alkalinity and lifts pH only a little. Use it when both are low; use soda ash when only pH is low.
Why does my pool pH keep dropping? Usually low alkalinity (under 60 ppm lets pH swing), trichlor tablets or a lot of rain. Raise alkalinity to 60–100 ppm and pH holds much better.
Does soda ash make the water cloudy? It can for a few hours if a lot goes in at once, or when calcium is high. Add it slowly, dissolved first, in front of a return jet.
How long after adding pH Up can I swim? Once it has mixed in with the pump running — follow the time on your product’s label.
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