2000 Complete, Alkalinity/Chlorine (hi range), FAS-DPD/CYA/Hardness/pH
K-2006C with 2oz Solutions
In recent years, professionals in the pool and spa industry have progressed from using orthotolidine (OT) to N,N-diethyl-p-phenylene-diamine (DPD) when determining chlorine levels with color-matching tests. The OT method only measures total chlorine—the sum of active and spent sanitizer—which makes maintaining the correct residual a guessing game. Because of this, regulatory authorities do not permit OT testing in commercial pools. In addition, orthotolidine contains hydrochloric acid, making it more costly to ship than DPD and therefore more costly to buy.
Analyte | System | Method/Chemistry | Standard/Equivalance or Description | Comparator | Cell |
---|---|---|---|---|---|
Alkalinity, Total | Drop test | Blended indicator | 1 drop = 10 ppm total alkalinity as CaCO?éâ | 9058 | NA |
Chlorine, Free & Combined | Drop test | FAS-DPD | 1 drop = 0.2 or 0.5 ppm chlorine (Cl?éé) | 9058 | NA |
Cyanuric Acid | Visual determination | Turbidimetric | 30, 40, 50, 60, 70, 80, 90, 100 ppm CYA | 9058 | NA |
Hardness, Calcium | Drop test | EDTA titration (includes inhibitors to prevent metal interference) | 1 drop = 10 ppm calcium hardness as CaCO?éâ | 9058 | NA |
pH w/ acid/base demand | 2000 Series comparator | Phenol red | 7.0, 7.2, 7.4, 7.6, 7.8, 8.0 | 9058 | NA |
Test Parameter | Description |
---|---|
Calcium, Magnesium, Total Hardness | Metal ions may cause interference; to prevent, add titrant containing EDTA to sample before buffer and indicator, then test as normal making sure to count drops of titrant added initially in total required to reach endpoint. If interference still occurs, dilute sample with DI water as necessary and retest. |
Chlorine | Chlorine levels > approx. 25 ppm may bleach out indicator or cause sample to develop a brown color; to prevent, add more DPD powder or dilute sample with DI water as necessary and retest. Other halogens and oxidized manganese may cause positive interference. |
pH | Iron > 10 ppm may cause negative interference. |
pH | Sanitizer levels > approx. 10 ppm may cause a blue-purple color resulting in false high readings. Wait for sanitizer level to decrease to normal levels and retest to assure an accurate reading. |
Total Alkalinity | High halogen level may change indicator reaction from green/red to blue/yellow; to prevent, add thiosulfate prior to testing. |
REAGENT SHELF LIFE
All reagents have a shelf life, whether they are liquids, powders, crystals, tablets, or test-strip pads. If kept dry, powders and crystals are very stable; acids are also long lived. Date of manufacture is not the controlling factor when it comes to shelf life—storage conditions are more important. As with all perishables, reagents are sensitive to environmental influences and will last longer under controlled conditions.
To this end, we recommend:
- Storing reagents at a consistent temperature in the range if 36°–85°F (2°–29°C); extreme temperature fluctuation, say from a refrigerator to a hot car trunk, causes reagents to deteriorate.
- Keeping them out of prolonged direct sunlight. (Note: their brown plastic bottles help protect very light-sensitive reagents.)
- Segregating reagents from containers of treatment chemicals.
- Replacing caps immediately and tightening them carefully so that exposure to air and humidity is limited.
- Avoiding switching bottle caps, placing bottle caps on soiled surfaces, repouring reagents into contaminated containers, or touching test strip pads.
Taylor formulates its reagents to remain effective for at least one year, with only very few exceptions (molybdenum indicator in liquid form is one; after four months old it should be tested against a standard periodically). As a general precaution, replace all reagents more than one year old, or at the beginning of a new testing season.
Addition Information
Instructions
Product Brochure
FAS-DPD Product Brochure