Test Methods: 1. Immerse the reaction area of the test strip in the test solution for 1-2 seconds, remove the test strip, and shake off excess water. 2. After 1 minute, compare the reaction area of the test strip with the color of the color chart to determine the test value of the test solution. 3. Colorimetric time should be controlled at about 60s. If the time is too long or too short, it will affect the reading. Specification: Accuracy: 96% Advantage: Anti- interference ability note: 1. Do not touch the test area of the reagent strip. 2. After removing the test strip, keep the remaining test strips sealed and protected from light. 3. Try to keep the liquid to be measured colorless or light-colored. Scope of application: Suitable for drinking water, aquarium, fish tank, swimming pool and spa, industrial water, pond, hot , etc 9 kinds of tests: total alkalinity/pH/hardness/iron/copper/lead/nitrate/nitrite/fluoride Material: plastic colour: As shown Package Contents: 100 x test strips Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.