Feature: The most suitable environment for fish is weak alkaline environment, freshwater aquaculture generally requires 6.5-8.5, and the most suitable range is between 7.5-8. Too high or too low PH is not good for fish growth. If the pH value is less than 4.4, the fish mortality rate can reach 7% to 20%. When the pH value is higher than 10.4, the mortality rate can reach 20% to 85%. When the pH value is higher than 10.6, it can cause all deaths. When the pH is only lower than 6.5, the oxygen-carrying ability of the blood of the animal will be reduced, resulting in physiological hypoxia, a decline in the metabolic function, and a decline in the immune function; Breathing ability and mass death. Storage conditions and validity period: 1. Product validity period: Store in a dry place away from light, and the validity period is 24 months. 2. Validity period for opening the bottle: After opening, the cap of the cylinder should be sealed and stored in a dry place away from light. The validity period is 90days. Package Included:100Pcs/Set x Water Quality Test Paper Testing method: 1. Immerse the reaction area of the test strip in the solution to be tested for 1-2 seconds, take out the test strip, and drain off the excess water on it. 2. After 30 seconds, compare the reaction area of the test strip with the color of the colorimetric card to determine the test value of the solution to be tested. 3. The colorimetric time should be controlled at about 60s, if the time is too long or too short, the reading will be affected. Parameter: Accuracy: 96% Shelf life: 2 years Material: PET Test time: 30 s Advantage: With anti-VC interference ability Testing element: Total hardness, alkali, cyanuric acid, nitrate, nitrite, residual chlorine, pH Scope of application: suitable for fish ponds, fish tanks, aquaculture, etc. Precautions: 1. Do not touch the reaction end of the test strip when taking out the test strip, so as not to contaminate the test strip and affect the test results. 2. After taking out the required number of test strips, keep the remaining test strips sealed and protected from light. 3. The liquid to be tested should be kept as colorless or light-colored as possible. Before testing, the liquid with too dark color can be adsorbed with activated carbon for dehydration treatment. If the liquid to be tested is turbid, let it stand for a period of time, and then take the clear part for testing after precipitation.