Installation manual
SOME TIPS ON WATER CHEMISTRY
Some Tips on Water Chemistry
How to adjust pH.
A pH range of 7.2 – 7.6 is ideal for maximum comfort and maximum chlorine
effectiveness. Always adjust total alkalinity before adjusting pH.
Low pH (acidic water) leads to stinging eyes and corrosion of open metal fittings. Raise
the pH by adding sodium bicarbonate or soda ash. Consult your pool
professional regarding which chemical is best for your situation and the proper
amount to use. Check the pH after 4 hours of circulation, adjusting as necessary
to achieve the proper range.
High pH (alkaline water) leads to clouding of the water and reduces the amount of
active chlorine. This means algae and bacteria can grow. Lower the pH by adding muri-
atic acid to the pool water. The acid demand indicated by your 4-in-1 test kit
will show the amount of acid to use. WARNING: ALWAYS ADD ACID TO WATER,
NEVER WATER TO ACID.
If your pH remains inconsistent, check your total alkalinity.
Total alkalinity affects pH
Total alkalinity is a measure of the alkaline chemicals in your pool water (e.g. Bicar-
bonates, carbonates, and hydroxides). It can be thought of as the buffering system
necessary to control pH. Low alkalinity can be compared to weak shock absorbers on
a car, allowing pH to fluctuate. The pH will be difficult to maintain and staining of pool
surfaces may occur when total alkalinity is too low.
Total alkalinity should be in the range of 100-120 ppm. Total alkalinity is often confused
with pH, which it affects.
To raise total alkalinity, add pH buffer (sodium bicarbonate) at the rate shown in the
manufacturer’s instructions to achieve a reading in the 100 – 120 ppm range. 180 g of
sodium bicarbonate raises 10,000 litres of pool water by 10 ppm.
To lower the total alkalinity, use muriatic acid. The acid demand chart in your 4-in-1
test kit indicate the necessary amount to add. Adjust as needed until the reading (taken
at least 24 hours later) is in the 100-120 ppm range. When total alkalinity is correct,
you may need to adjust pH. WARNING: ALWAYS ADD ACID TO WATER, NEVER
WATER TO ACID.
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