Testing the Water
Pool chemistry is affected by many different factors including bathers, chemical additions and environmental influences. Because conditions in a pool change constantly, testing is vital to ensure proper water balance and sanitizer levels. Pool side test kits are available to assist the operator in maintaining water quality.
- Obtain an appropriate water sample. The water sample for testing should be taken in a clean, plastic container approximately 18 inches below the water’s surface.
- Do NOT gather the sample in the testing vial itself. It’s easier to capture the sample in a container then decant the water into the testing vials.
- The sample should be taken from an area of the pool that is away from skimmers and return AND should be taken from the same location every time. In larger pools (surface area greater than 1000 square feet), multiple samples should be tested from different areas of the pool.
- When using test strips, never dip the strip directly into the pool. Dip the strip into the sample captured from the pool and always obtain a fresh sample for each test strip test.
- Fill the testing vials to the appropriate level marked on each vial, filling the vial so that the bottom of the meniscus (the bottom of the natural arc that the water creates at the top of the sample) is on the water fill line.
- Hold the testing vial at eye level to get the most accurate volume.
- If using color blocks to compare colors, use a neutral colored (white) background behind the blocks and face away from the sun (sun should be behind you) to get the most accurate color assessment. Do NOT use fluorescent lighting when making color comparisons.
- When using a dropper to apply the reagent or titrant, hold the dropper vertical (straight up and down) and gently squeeze out one drop at a time in order to deliver the proper amount of liquid to the sample.
- Store test kits, reagents, and test strips in a cool dark location and away from other chemicals (especially oxidizers).
- Tighten the caps securely on the reagents after each use.
- Replace reagents and test strips every year.
It is important to check state and local codes to determine the acceptable test methods and frequency of testing for commercial facilities.