PRODAC TEST KH for measuring the carbonate hardness of aquarium water.

Rinse the water sample test tube several times with the water to be tested and then fill it with a 5 ml water sample.

Add one drop of the reagent contained in the bottle and gently shake to mix the solution after each drop.

Count the number of drops until the solution changes from yellow to red-purple.

Once it turns red-purple, let it stand for 30 seconds.

If the color fades, add more drops of reagent until the solution remains red-purple.