About This Accuracy: 0.5 pH; Litmus papers are used to determine the pH level of a liquid and determine if a solution is acidic, basic, or neutral Advantage: There are 8 color-coded scales that go from 5.5 to 9. Also can be used to determine the strength of acid and base, as we go from 9 to 5 the acidity of the solution increases Instruction: Dipping the pH paper into a solution and observing the change in color of the paper. After one second, compare it with the standard color cards and read the pH value. The smaller the pH value, the stronger the acidity, the higher the pH value, the stronger the alkalinity, when the pH value is 7, the solution is neutral Application: Widely used for industrial chemical testing, science education, laboratory use, drinking water, swimming pool, spas, aquariums, and classroom analytical chemistry NOTE: The test strip itself is yellow. Not applicable for oil and acid-base solutions with a concentration of less than 0.01%. Should be stored in a dry place protected from light Overview Brand : PATIKIL Ph Range : 5.5-9.0 Recommended Uses For Product : Aquarium, Home Water, Litmus Test, Spa, Swimming Pool, Water Test, ph Test Unit Count : 1.0 Count Manufacturer : PATIKIL