Shake the reagent bottle well before use! Do not allow the tested water to come into contact with aquarium or pond water!
1. Rinse the bottle several times with the water to be tested, then fill it up to the 5 ml mark. Dry the outside of the bottle. 2. Add the reagent drop by drop. Gently shake the bottle after each drop, until the color changes from red to brown and then to green. 3. The number of drops used from the reagent represents the total hardness present (in degrees °dGH). For example, 5 drops = 5°dGH. 4. Cleaning: Rinse the bottle thoroughly with tap water before and after each test. Close the reagent bottle immediately after use. Store it at room temperature and away from light. Keep it closed and out of reach of children. For testing only in ornamental aquariums and pond water.

Usage information in the United States Most ornamental fish come from countries where the soil is poor in minerals. However, the situation is quite the opposite in many other regions around the world. Rainwater dissolves calcium and magnesium from the soil, thus creating hard water. With the sera gH test, you can determine the total hardness accurately and quickly. Considering natural conditions helps in selecting the optimal stock of fish for the community tank, which is a prerequisite for successful breeding. High levels of total hardness can be reduced by mixing demineralized water. Combining Sera Aquatan and Sera Blackwater Aquatan or filtering through Sera Super Peat will create soft water, as required for most South American fish (such as those from the Amazon basin).