pH Bounce
pH bounce is the condition where pool water pH swings rapidly and unpredictably, typically caused by insufficient total alkalinity.
Definition
pH bounce is the condition where pool water pH swings rapidly and unpredictably, typically caused by insufficient total alkalinity.
Typical Values: Occurs when TA is below 60 ppm
In Plain Language
When total alkalinity is below 60 ppm, the buffering capacity of the water is inadequate. Small additions of acid or base, rain, or even bather activity can cause pH to swing by 0.5–1.0 units. The symptom is a pH that was corrected yesterday but is out of range again today. The fix is always to raise total alkalinity to 80–120 ppm first, which stabilises the buffering system.
Why It Matters
pH bounce is frustrating and wasteful. Understanding the root cause (low alkalinity) prevents weeks of fruitless pH chasing.
Typical Values
Occurs when TA is below 60 ppm
Last reviewed: 2026-06-01