BioGuard Soft Swim Test Strips are designed to test pool water for the chemicals used in the Soft Swim program. These strips are easy to use and reveal results quickly and accurately. Pool experts recommend that Soft Swim Test Strips should be used weekly to ensure properly balanced water. This product works only with pools on the Soft Swim program. Each Soft Swim product is formulated to work specifically with the biguanide chemistry of the Soft Swim program. Directions Dip Strip into water for 1 second, remove. Hold strip level for 30 seconds. Compare total alkalinity, pH, and SoftSwim C (in that order) to the color chart. Re-Dip the strip and rapidly move strip back and forth underwater for 30 seconds. Compare bioguanide part to color chart.