Owner`s manual

WATER CHEMISTRY TERMS YOU SHOULD KNOW
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Before jumping into the Spa Water Maintenance, here are some terms to help you.
1. Parts per million, or ppm: This is a form of measurement used in most spa chemical
readings. Best described as any one million like items of equal size and make up, next
to one unlike item, but of equal size. This would be one part per million.
2. Total Alkalinity: This is a measurement of the ability of the water to resist changes in
pH. Put another way, it is the water’s ability to maintain proper pH. Total alkalinity is
measured in parts per million from 0 to 400 plus, with 80 to 120 ppm being the best
range for spas. With low alkalinity, the pH will flip, or change back and forth, and be
hard to control. With high alkalinity it becomes extremely difficult to change the pH.
3. pH or potential hydrogen: This is a measurement of the active acidity in the water, or it is
the measurement of the concentration of active hydrogen ions in the water. The greater
the concentration of active hydrogen ions, the lower the pH. pH is not measured in
parts per million, but on a scale from 0 to 14, with 7 being the neutral. In spas when
ever possible, a measurement between 7.2 and 7.8 is best. Whenever possible, it should
be between 7.4 and 7.6. With low pH, the results can be corroded metals, etched and
stained plaster, stained fiberglass or acrylic, eye / skin irritation, rapid chlorine or bromine
loss, and total alkalinity destruction. With high pH, the results can be cloudy water, eye /
skin irritation, scale formation and poor chlorine or bromine efficiency.
4. Shocking: This is when you add either extra chlorine (superchlorinate) by raising the chlo-
rine level above 8 ppm, or add a non-chlorine shock (potassium monoperoxysulfate or
potassium monopersulfate) to burn off the chloramines or bromamines. A non-chlorine
shock acts by releasing oxygen in the water, which serves the same function as chlo-
rine. The advantage to using non-chlorine shock, is you can enter the water within 15
minutes after shocking. Using chlorine, you must wait until the total chlorine reading is
below 5 ppm. One thing to remember, a non-chlorine shock will not kill bacteria or dis-
infect.
5. Sequestering: This can be defined as the ability to form a chemical complex which
remains in solution, despite the presence of a precipitating agent (i.e. calcium and met-
als). Common names for sequestering chemicals are; minquest, stain and scale control,
metal-x, spa defender, spa metal gone, (etc.).
6. Filtration: Filters are necessary to remove particles of dust, dirt, algae, etc. that are
continuously entering the water. If the spa is not operated long enough each day for
the filter to do a proper job, this puts a burden on the chemicals, causing extra expense.
A spare cartridge should be kept on hand to make it easy to frequently clean the
cartridge without the need for a long shut down. This will also allow the cartridge to
dry out between usages, which will increase the cartridge life span as much as twice.
Replace the cartridge when the pleats begin to deteriorate. Cartridge cleaning should
be done a minimum of once a month. More often with a heavy bather load.