Hanna Instruments

How do you use the Hanna Alkalinity Checker Colorimeter?

  1. Use a screwdriver to remove the battery cover and install the included battery.
  2. Fill the included cuvette with 10 mL of your aquarium water, this is your sample. Tighten cap.
  3. Holding the cuvette by the ends, wipe the glass cuvette free of water, fingerprints, or any other blemishes with a dry cloth.
  4. Push the ON/OFF button to turn on the Checker. When C1 is on the display place the water sample into the Hanna Checker.
  5. Press the ON/OFF button and wait for C2 to display
  6. Remove the water sample and add the appropriate amount of reagent into the sample cuvette, re-tighten the cap.*
  7. Gently invert the cuvette a few times to mix it, do not shake or create bubbles. Wipe the cuvette clean again using a towel.
  8. Place water sample back into the Hanna Checker, push the ON/OFF button.
  9. Wait for reading to display. Be sure to write down the reading, you only have 2 minutes before the checker automatically turns off.

*When drawing up reagent into the syringe, only the tip attachment will fill with fluid, this is normal. The tip is designed to hold exactly 1mL of fluid. It is also very important for the cuvette to be free of fingerprints and smudges to obtain an accurate reading.

What should the dKH be in a reef tank?

The entire safe range is 7 - 12 dKH and most tanks will target 8 - 9 dKH. Just remember, the most important thing here isn't the exact number you choose rather how well you maintain that stability. Your alkalinity should not fluctuate any more than 0.1 - 0.3 ppm daily; ideally, that number stays rock solid. Allowing fluctuations of more than 1.0 dKH will cause stress for tank inhabitants. 

Watch Video: New concept in reef tank Alkalinity: How it works & how to gain 70% or more coral growth!

How do you calibrate the Hanna Alkalinity Checker Colorimeter?

Technically, the calibration occurs with every test you perform. The meter calibrates itself when you first insert the water sample before adding the reagent.  

Alternatively, you can use the Alkalinity Reference Set in order to verify your meter is reading accurately. 

How accurate are the Hanna Checkers?

If you follow the instructions and perform your test correctly, the accuracy range is +/- 0.3 dKH.  The cuvette needs to be clean and free of smudges and the water temperature should be at or close to 77° F in order to achieve the most accurate results.

What is the range of measurement of the Hanna Alkalinity Checker Colorimeter?

Range: 0.0 - 20.0 dKH