LaMotte Pool & Spa Owner's Handbook - Manual (Page 4)

WHY YOU SHOULD TEST THE WATER
The two most important reasons to test the water:
#1 To protect the bather
The goal of every pool and spa owner is to have sparkling, clean water.
Unfortunately, a variety of undesirable substances will often enter a pool
or spa. Such items can make the water unhealthy. There are bacteria
on every person’s body that can get into water; some forms can cause
infections or rashes. Bather perspiration and urine break down to
undesirable nitrogen compounds and “Mother Nature” can also
contribute: rain, algae spores, leaves and other organic materials. All of
these necessitate the use of a sanitizer, such as chlorine. The Insta-Test 5
color chart shows the ideal range for free chlorine and total chlorine in
swimming pools. Spa owners should keep in mind that the ideal free
chlorine range in spas (hot tubs) is between 2 and 4 ppm.
#2 To protect the pool or spa
Everything that the water contacts is affected by the chemistry of the
water itself. The surfaces of the pool or spa, the heater, the filter, the steps,
and the pump can be damaged if the water is either corrosive or scale
forming. The goal of the water analyst is to keep the water “in balance”
so it does not damage the pool and its equipment. By maintaining each
test factor of pH, alkalinity, and hardness within the “Ideal Range” [shown
on the test strip color chart] the water will not harm the pool
or spa surfaces and components.
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