347
PO
S AVE THESE INSTRUCTIONS
(347PO) SPA ENGLISH 7.5” X 10.3” PANTONE 295U 05/21/2020
English
Page 17
SPA WATER CHEMISTRY AND BALANCE (continued)
SPA Water Adjustment
How to adjust the spa water chemistry when the levels are off the range.
CAuTION:
Always follow the
chemical manufacturer’s directions, and the health and hazard warnings.
Total Alkalinity (TA) Adjustment
Remove the spa cover to aerate the water and use the included test strips to check the chemistry level.
Ensure the chlorine level in the water is between 2-4 ppm first, as chlorine will affect the TA test result.
If the TA level (and not the pH) is higher than 120 ppm, to lower the TA level, you add muriatic acid (hydrochloric
acid) or sodium bisulfate.
If the TA level is lower than 60 ppm, you add sodium bicarbonate.
For example (for 4 adults’), if the TA level is 180 ppm, the desired decrease is 60 ppm, from below chart, you
need to add 0.269 Lb (121 g) of sodium bisulfate or 0.101 qt (96 ml) of muriatic acid.
If the test strip color is between 180 ppm and 240 ppm, and close to 180 ppm, you can also add 0.269 Lb
(121 g) of sodium bisulfate or 0.101 qt (96 ml) of muriatic acid.
If the reading is more than 240 ppm, you can add sodium bisulfate or muriatic acid to the water drop by drop
until the test strip indicates a 240 ppm reading, then add 0.528 Lb (238 g) of sodium bisulfate or 0.202 qt
(192 ml) of muriatic acid.
NOTE:
After adjustment, retest the water after 24 hours and adjust again if necessary.
Desired level
60 ppm
80 ppm
100 ppm
120 ppm
140 ppm
Volume:
210 gal / 795 L
0.269 Lb
0.358 Lb
0.448 Lb
0.528 Lb
0.627 Lb
121 g
161 g
202 g
238 g
283 g
Volume:
290 gal / 1098 L
0.368 Lb
0.492 Lb
0.614 Lb
0.737 Lb
0.860 Lb
168 g
224 g
279 g
335 g
391 g
Lowering Total Alkalinity
Amount of Sodium Bisulfate to lower Total Alkalinity
Desired level
20 ppm
40 ppm
60 ppm
80 ppm
Volume:
210 gal / 795 L
0.059 Lb
0.118 Lb
0.178 Lb
0.237 Lb
27 g
53 g
80 g
107 g
Volume:
290 gal / 1098 L
0.081 Lb
0.162 Lb
0.244 Lb
0.326 Lb
37 g
74 g
111 g
148 g
Raising Total Alkalinity
Amount of Sodium Bicarbonate to raise Total Alkalinity
Desired level
60 ppm
80 ppm
100 ppm
120 ppm
140 ppm
Volume:
210 gal / 795 L
0.101 qt
0.135 qt
0.169 qt
0.202 qt
0.234 qt
96 mL
128 mL
160 mL
192 mL
223 mL
Volume:
290 gal / 1098 L
0.139 qt
0.185 qt
0.232 qt
0.278 qt
0.324 qt
132 mL
176 mL
220 mL
264 mL
308 mL
Amount of Muriatic Acid to lower Total Alkalinity
(Muriatic acid: 31.45%)
pH Adjustment
After the total alkalinity has been lowered to 120 ppm or raised to 80 ppm and the pH is still high or low, you
can adjust it using the following chart.
