Carbonate Hardness Test Kits

KH is a measure of carbonate hardness in water.  Put simply KH is the waters ability to hold on to acidity and stabilize pH.   If your KH is out of range, you will be unable to keep a constant pH level which will cause severe stress to aquatic life and is often seen to be the cause of Blackbeard algae.  The ideal KH range for freshwater aquariums is 70 to 140ppm.

GH refers to general hardness and is a measure of dissolved mineral salts such as calcium and magnesium.  Ideally your aquarium GH should be between 70 and 140ppm, however some fish like goldfish, livebearers and African Cichlids like higher GH levels.

The Rikka GH KH pH test kit is an easy to use  lab grade kit that enables you to accurately and quickly measure these parameters.

Always hold the dropper pointing vertically downwards when taking drops from the bottle. The external surface of dropper should be dry. Avoid bubbles. Failure to follow these precautions may lead to deviations in the test results.

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Determination of GH:
1.Wash measuring vial few times with water that is to be tested.
2. Add 5ml of water that is to be tested to measuring vial.
3. Add the reagent drop by drop counting them, until colour change from red to olive-green.
4. Each drop is equal to 1 German degree of total hardness.

Immediately after measuring water hardness, thoroughly wash the measuring vial.

Determination of KH:
1.Wash measuring vial few times with water that is to be tested.
2. Add 5ml of water that is to be tested to measuring vial.
3. Add the reagent drop by drop counting them, until colour change from blue to yellow.
4. Each drop is equal to 1 German degree of carbonate hardness.

Immediately after measuring water hardness, thoroughly wash the measuring vial.

Determination of pH:
1.Wash measuring vial few times with water that is to be tested.
2. Add 5ml of water that is to be tested to measuring vial.
3. Add 5 drops of solution and shake vigorously.
4. Compare the colour with included colour scale.

Immediately after measuring acidity, thoroughly wash the measuring vial.

Discard indicator solution or water after testing.

In order to get accurate measurements, the temperature of water that is to be tested must be 25±3°С, and room temperature must not be below 20°С.

  • Storage life: 24 months, but no more than 12 months since opening.
  • Keep at 10-25°С in dry dark place! Keep out of reach of childrenі!
  • Avoid skin contact! Upon skin contact wash with large amounts of water!