Each kit will give you 120 tests. 

1. Using the 5 ml syringe add 5 ml of aquarium water to the test vial.

2. Add 5 drops of GH-1 solution to the test vial and swirl a little.

3. Using the 1 ml syringe, place the needle firmly and  draw up the GH-2 solution until the lower end of syringe's black rubber is right on the 1.00 ml mark.

• Before this step, ensure that the needle is empty of liquids and that it's submersed in the solution the entire time to avoid air entering to the syringe.

• The presence of a small layer of air between the liquid and the black part of syringe is normal and will not affect the result.

4. Add 1 drop of GH-2 solution from the syringe to the test vial. The color of the tested water will change to pink: 

5. Continue adding GH-2 to the test vial one drop at a time swirling a little after each drop until the color change to Navy Blue: 

6. Read the position of the lower black rubber syringe. (Each division corresponds to 0.01 ml) and obtain your GH value from the GH chart.