13
Index
Water Balance
Condition
Recommendation
Below 9.6
Highly Corrosive
9.6 to 10.5
Corrosive
Increase pH to 7.5 - 7.8.
Increase Calcium Hardness to at least
50 mg/l.
Increase Total Alkalinity to 100 mg/l
or higher as necessary.
Retest Water Balance.
10.6 to 10.9
Acceptable Balance
Retest water regularly.
11.0 to 11.2
Ideal Balance
No action required.
11. 3 to 11.6
Acceptable Balance
Retest water regularly.
11. 7 to 12.6
Scale Forming
Above 12.6
Highly Scale Forming
Decrease pH to 7.2 - 7.5.
Decrease Total Alkalinity to 150 mg/l or
lower as necessary.
Retest Water Balance.
NOTES
1 The test has been calculated for an average heated swimming pool
(82°F, 28°C). For unheated swimming pools, subtract 0.1 from the index value
obtained, for high temperature pools and spas, add 0.1 to the index value
obtained.
2 Always keep the pH, Total Alkalinity and Calcium Hardness levels within the limits
recommended in pool operating instructions and chemical suppliers'
recommendations. Seek specialist advice if corrosion or scale formation is still
apparent even though the water is shown to be in a balanced condition.
TDS Test
TOTAL DISSOLVED SOLIDS
Range 0
-
10,000 mg/l
TDS Sensor (Optional Extra)
The total dissolved solids reading is taken using the TDS Sensor (PT 153/S). This
model is specially calibrated for swimming pool water.
1 Pour about 20 ml of pool water into the Sample Container (PT 510).
2 Remove protective cap from the end of the TDS Sensor. Turn on the sensor.
3 Dip the sensor into the water in the container.
4 Note the reading on the sensor display. Multiply this result by 100. The
result obtained represents the TDS content of the pool water in mg/l (ppm).
5 Remove the sensor, rinse probe in clean water. Switch off and replace cap.
