Water Chemistry Terms - Master Spas LSX 700 Owner's Manual

WATER CHEMISTRY TERMS YOU SHOULD KNOW
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 pool or 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. Average size spa: What is it? The national spa and pool institute (NSPI) states; 350 to 400 U.S.
gallons is average. As a general rule, chemical dosages are the same for any spa between 100
and 500 U.S. gallons. Spas over 500 U.S. gallons the dosage would be double. Under 100
U.S. gallons would be on a case by case basis.
3. 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 150 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.
4. 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 forma-
tion and poor chlorine or bromine efficiency.
5. Shocking: This is when you add either extra chlorine (superchlorinate) by raising the chlorine
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 chlorine. 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 remem-
ber, a non-chlorine shock will not kill bacteria or disinfect.
6. 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 metals). Common
names for sequestering chemicals are; minquest, stain and scale control, metal-x, spa defend-
er, spa metal gone, (etc.).
7. Filtration: Filters are necessary to remove particles of dust, dirt, algae, etc. that are continu-
ously 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. Filtration time will
depend on the spa size, pump and filter size, and of course, bather load. 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.
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