LaMotte Pool Manager Water Quality Handbook - Manual (Page 13)

pH
What is pH?
The term pH refers to
the concentration of
hydrogen ions in water.
The pH test determines
if a substance is acidic,
neutral or basic. A
substance with a pH of
7.0 is neutral, neither
acidic nor basic. Those
with a pH of less than
7.0 are acidic (orange
juice has an acidic pH of
4.2). A pH above 7.0 is
basic (ocean water is basic with a pH of about 8.0). The
ideal pH for pool water is slightly basic, between pH 7.2
and 7.6. This range is most comfortable for the
swimmer, protects the pool equipment, and allows
sanitizers to work efficiently.
Why Do We Test pH?
The pH test is critical to protecting the pool. Though
low or high pH levels can irritate swimmers’ eyes or skin,
pH is normally considered the best indicator of overall
“pool health.”
Controlling pH is critical for protecting the pool and its
equipment from costly damages due to corrosive/acidic
water or scale-forming/basic water.
For an indication of just how the pH affects the overall
condition of the pool and its parts, other tests must be
performed to obtain a clear answer. These tests are
discussed later.
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0
Basic
Neutral
Acidic
Bleach
Ocean Water
Pool Water
Orange Juice
Trichlor
(liquid Cl )
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