1. General: PH test strips help maintain good health and can be used to test lemon juice, milk, soap, detergents, etc. Acid-base test strips are commonly applicable to swimming pool water, cosmetics, school courses, and laboratories. 2. Testing range: The pH level of swimming pool pH test strips ranges from 1 to 14: 1 - 3 is very acidic, 4 - 6 is acidic, 7 is neutral, 8 - 11 is alkaline, and 12 - 14 is very alkaline. 3. Quick results: Put the litmus paper into the liquid. Read the result after about 15 seconds and compare it with the pH color chart. 4. Concentration limit of pH test strips: When the concentration of the acid or alkaline solution is lower than 0.01%, the test strips cannot show the acidity or alkalinity. 5. Packaging includes: A pack of pH 1 - 14 color chart contains 80 pH test strips, and 6 packs contain 480 pH test strips for acid pools.