LaMotte Pool Manager Water Quality Handbook - Manual (Page 35)

Regular maintenance doses of the algicide and oxidizer are
recommended. Check the manufacturer’s recommendations for
dosages.
Salt Chlorinators
Chlorine can be produced by applying a low voltage
direct current to salt (sodium chloride). If sodium
bromide salt is used, bromine will be produced.
The salt can be in a separate brine tank or in the pool
water. There are minimum concentrations of salt
required, usually 2,000-6,000 ppm – follow the
manufacturer’s recommendations. It is also important to
size the units properly so that enough halogen is
produced to meet the demand.
To test the salt concentration, one can use a field kit or a
test strip.
Hot Water
The chemistry of pools and spas is similar, but there are
some things to keep in mind when working with hot
water systems. Since there is a much smaller volume of
water, the bather load is much higher. This leads to an
increase in bacteria and waste products. Chemical
reactions are faster at higher temperatures. Calcium
carbonate is less soluble, so the tendency for scaling and
cloudy water is greater. Particular consideration must be
given to the heater element, where the water
temperature is higher than the rest of the spa. Scale will
form on this before it forms elsewhere in the system.
The higher temperatures also provide a better
environment for some bacteria. Pseudomonas is a type
of bacteria that frequently causes skin rashes in hot
water. Because of this, hot water systems need higher
sanitizer concentrations and should be shocked
regularly.
Jetted spas and tubs can force carbon dioxide from the
water. This causes the pH to increase. Because of
evaporation and chemical addition, the TDS will
increase faster than in a pool. TDS is a good way to
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