LaMotte Pool & Spa Owner's Handbook - Manual (Page 21)

STAINS
When stains appear on swimming pool surfaces, immediate action should
be taken to avoid costly and annoying repairs. Brushing can often remove
fresh stains if recognized early enough. Neglected stains in plaster pools
may ultimately require draining and an acid wash. Like colored water,
stains are the result of metal ions in pool water. Stains indicate that either
the source water contains metals, such as copper, iron, or manganese,
or that a corrosive pool water condition is dissolving metal pool
components.
The first step after noticing a pool stain is to determine what caused the
stain. This is done by having your local dealer or service professional test
the pool water for metals. If the stain is caused by metals, the dealer may
recommend either a sequestering agent or clarifier to treat the problem.
If metals are present due to improper pH levels, the pH should be adjusted
to be within the range of pH 7.2-7.6. If the problem persists, add a
sequestering agent or a clarifier that will chemically bind the metals so
that they can be filtered out before they cause more staining problems.
COLOR BLUE/GREEN RED/BROWN BLACK
CAUSES Copper or iron
corrosion or from
water supply. Iron or manganese
corrosion or from
water supply. Manganese in water
supply.
TREATMENT 1. Adjust pH & alkalinity to recommended ranges.
2. Vigorously brush the stained areas.
3. Add sequestering agent & run filter.
4. Two days later, shock treat the water.
5. Retest pH & alkalinity. Also test hardness levels and if
necessary, raise to 200 ppm.
Notes:
Take a pool sample to a pool professional for dissolved metals testing 24-48
hours after treatment and at least once a month.
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