Water Chemistry Terms - Master Spas LEGEND LSX700 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:
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:
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:
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:
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.
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 remember,
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 defender, spa
metal gone, (etc.).
7. 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. 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.
DO NOT DIVE.
This is a form of measurement used in most pool or spa chemical
What is it? The national spa and pool institute (NSPI) states; 350 to 400 U.S.
This is a measurement of the ability of the water to resist changes in pH. Put
This is a measurement of the active acidity in the water, or it is
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