pH Control
pH is used to measure a relative balance between acid and base (alkaline) in swimming pool water. The pH scale ranges from 0 to 14, with the number 7 being neutral. From 7 to 0 indicates an increasingly acidic condition and from 7 to 14 indicates an increasingly alkaline condition.
Proper pH Control
Proper pH control is essential to the correct operation of a pool. The pool operator must take a responsible attitude toward maintaining pH in the desired range of 7.4 to 7.8. Pool water that has a pH higher than 8 (alkaline) will retard the sanitizing effect of the chlorine. The pool water becomes cloudy and alkaline scale will form on the walls and equipment. On the other hand, a pH level below 7.0 (acidic) will dissipate chlorine rapidly and bathers will experience eye irritation and "crawly" skin. A low pH (acidic) will also corrode exposed metal pool parts.
To Lower pH Use:
- Liquid acid such as Muriatic Acid or
- OPAquatics Pool Brite pH Control Minus (dry acid) or
- CO2 (Carbon Dioxide) Gas
Follow the directions on the Taylor 2000 Acid Demand Test and refer to Table D for dry acid or Table E for liquid acid.
To Raise pH:
Use OPAquatics Pool Brite pH Plus (Soda Ash).
Follow the directions on the Taylor 2000 Base Demand Test and refer to Table C.
Table C
To Raise pH using the Taylor Base Demand Procedure
Adjustment Compound Used is Soda Ash (Sodium Carbonate).
| Gallons of Water in Pool | Drops of Taylor Base Demand Reagent* | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
| 2,500 | 1.25 oz. | 2.5 oz. | 3.75 oz. | 5.0 oz. | 6.25 oz. | 7.5 oz. | 8.75 oz. | 10 oz. | 11.25 oz. | 12.5 lbs. |
| 5,000 | 2.5 oz. | 5 oz. | 7.5 oz. | 10 oz. | 12.5 oz. | 15 oz. | 1.09 lbs. | 1.25 lbs. | 1.41 lbs. | 1.56 lbs. |
| 10,000 | 5 oz. | 10 oz. | 15 oz. | 1.25 lbs. | 1.56 lbs. | 1.8 lbs. | 2.2 lbs. | 2.5 lbs. | 2.8 lbs. | 3.1 lbs. |
| 15,000 | 7.5 oz. | 15 oz. | 1.41 lbs. | 1.8 lbs. | 2.3 lbs. | 2.8 lbs. | 3.3 lbs. | 3.8 lbs. | 4.2 lbs. | 4.7 lbs. |
| 20,000 | 10 oz | 1.25 lbs. | 1.8 lbs. | 2.5 lbs. | 3.1 lbs. | 3.8 lbs. | 4.4 lbs. | 5 lbs. | 5.6 lbs. | 6.2 lbs. |
| 25,000 | 12.5 oz. | 1.6 lbs. | 2.3 lbs. | 3.1 lbs. | 3.9 lbs. | 4.7 lbs. | 5.5 lbs. | 6.2 lbs. | 7 lbs. | 7.8 lbs. |
| 50,000 | 1.56 lbs. | 3.1 lbs. | 4.7 lbs. | 6.2 lbs. | 7.8 lbs. | 9.7 lbs. | 10.9 lbs. | 12.5 lbs. | 14.1 lbs. | 15.6 lbs. |
* NOTE: With Taylor 2000 Test Block, use Taylor #R-0006 Base Demand Reagent only...Or...With #4024 11.5 mL. Rectangular Cell use Taylor #R-0862 Base Demand Reagent only.
Table D
To Lower pH using the Taylor Acid Demand Procedure
Using Dry Acid (Sodium Bisulfate) as a treatment chemical.
| Gallons of Water in Pool | Drops of Taylor Acid Demand Reagent* | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
| 2,500 | 0.16 lbs. | 0.28 lbs. | 0.5 lbs. | 0.63 lbs. | 0.75 lbs. | 1.0 lbs. | 1.13 lbs. | 1.2 lbs. | 1.5 lbs. | 1.6 lbs. |
| 5,000 | 0.31 lbs. | 0.56 lbs. | 1.0 lbs. | 1.25 lbs. | 1.5 lbs. | 2.0 lbs | 2.25 lbs. | 2.5 lbs. | 3.0 lbs. | 3.13 lbs. |
| 10,000 | 0.63 lbs. | 1.13 lbs. | 2.0 lbs. | 2.5 lbs. | 3.0 lbs. | 4.0 lbs. | 4.50 lbs. | 5.0 lbs. | 6.0 lbs. | 6.25 lbs. |
| 15,000 | 0.94 lbs. | 1.69 lbs. | 3.0 lbs. | 3.75 lbs. | 4.5 lbs. | 6.0 lbs. | 6.75 lbs. | 7.5 lbs. | 9.0 lbs. | 9.4 lbs. |
| 20,000 | 1.25 lbs. | 2.25 lbs | 4.0 lbs. | 5.0 lbs. | 6.0 lbs. | 8.0 lbs. | 9.0 lbs. | 10.0 lbs. | 12.0 lbs. | 12.5 lbs. |
| 25,000 | 1.56 lbs. | 2.82 lbs. | 5.0 lbs. | 6.25 lbs. | 7.5 lbs. | 10.0 lbs. | 11.25 lbs. | 12.50 lbs. | 15.0 lbs. | 15.6 lbs. |
| 50,000 | 3.125 lbs. | 5.63 lbs. | 10.0 lbs. | 12.5 lbs. | 15.0 lbs. | 20.0 lbs. | 22.5 lbs. | 24.0 lbs. | 30.0 lbs. | 31.25 lbs. |
20 oz. av. Dry acid = 1 pint liquid acid * NOTE: With Taylor 2000 Test Block, use Taylor #R-0005 Acid Demand Reagent only...Or... With #4024 11.5 mL. Rectangular Cell, use Taylor #R-0853 Acid Demand Reagent Only.
Table E
To Lower pH employing the Taylor Acid Demand Procedure
Adjustment Compound used is Muriatic Acid (Hydrochloric Acid- 20o Baume’)
| Gallons of Water in Pool | Drops of Taylor Acid Demand Reagent* | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
| 2,500 | ¼ CUP | ½ CUP | ¾ CUP | 1 CUP | 1 ¼ CUP | 1 ½ CUP | 1 ¾ CUP | 2 CUPS | 2 ¼ CUPS | 2 ½ CUPS |
| 5,000 | ½ CUP | 1 CUP | 1 ½ CUPS | 1 PINT | 2 ½ CUPS | 3 CUPS | 3 ½ CUPS | 1 QT. | 2 ¼ Pints | 2 ½ Pints |
| 10,000 | 1 CUP | 1 PINT | 1 ½ Pints | 1 QT. | 2 ½ Pints | 3 Pints | 3 ½ Pints | 2 QTS. | 4 ½ Pints | 2 ½ QTS. |
| 15,000 | 1 ½ CUPS | 1 ½ Pints | 2 ¼ Pints | 3 Pints | 2 QTS. | 2 ¼ QTS. | 2 ½ QTS. | 3 QTS. | 3 ½ QTS. | 1 GAL. |
| 20,000 | 1 PINT | 1 QT. | 3 Pints | 2 QTS. | 2 ½ QTS. | 3 QTS. | 3 ½ QTS. | 1 GAL. | 4 ½ QTS. | 1 ¼ GAL. |
| 25,000 | 1 ¼ PINT | 2 ½ Pints | 2 QTS. | 2 ½ QTS. | 3 QTS. | 1 GAL. | 4 ½ QTS. | 1 ¼ GAL. | 1 ½ GAL. | 1 ½ GAL. |
| 50,000 | 1 ¼ QT. | 2 ½ QTS. | 1 GAL. | 1 ¼ GAL. | 1 ½ GAL. | 2 GAL. | 2 ¼ GAL. | 2 ½ GAL. | 2 ¾ GAL. | 3 GAL. |
1 cup= 8 oz. liquid
* NOTE: With Taylor 2000 Test Block, use Taylor #R-0005 Acid Demand Reagent only...Or...With #4024 11.5 mL. Rectangular Cell use Taylor #R-0853 Acid Demand Reagent only.
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