Hanna Calcium Checker Review (8 Steps For Doing It Right)

This article will show you 8 steps to using Hanna Instruments Calcium Checker.

In this comprehensive guide I will cover:

  • Packaging and included equipment
  • How to use the checker step by step
  • Analyzing the results
  • And much more
hanna calcium tester


If you are currently keeping a reef tank, you know how important maintaining a proper level of calcium is for the health of your corals.

The Hanna calcium checker can be a bit confusing to use at first and many people are not using it properly. I often hear people say that the calcium reading of their saltwater tank seems to be off when using this tester.

The issue most of the time is the user not using it the right way. The tester itself is working fine. In order to get the most accurate calcium reading, it’s crucial that you perform each step the proper way. There is one step when performing the test that most people doing wrong. I will show you this exactly below.

There is no arguing that the Hanna checkers are one of the best testers on the market for saltwater aquariums. I am a huge fan of them. It can be difficult to get accurate readings from some hobby grade test kits but the Hanna testers will give you precise readings will all their testers.

Read my review of the Hanna Instruments alkalinity checker here.

Packaging And Included Equipment


Inside the Hanna Calcium test kit case, you will find the following:

  • Colorimeter HI758U supplied with 1 battery

The colorimeter is identical to the other Hanna devices, the only difference is the color. The Calcium checker is red. The LCD screen shows the test result and there is a hinged door on top that opens to insert the test sample. The door requires you to squeeze lightly in the center to open it.

The single AAA battery is accessible by opening the bottom cover using a Phillips screwdriver. Everything in the kit is solid and of great quality.

  • 2  Sample cuvettes with caps
  • Calcium reagent starter kit (25 tests included)
  • Dropper
  • 1 ml syringe with tip
  • 100 microliter pipette with tip
  • Plastic pipette
  • Instructions and guide


How To Use The Hanna Calcium Checker Step By Step


Using the Hanna Calcium checker is quite simple. As I mentioned earlier, some people say that this tester is not accurate but this is usually due to it not being used properly.


Step 1. Power on by pressing the black button. Wait to see ADD C1 on the screen.

Step 2. Use the 1ml syringe and add 1ml of reagent A to the cuvette.

Step 3. Use the dropper and fill the cuvette to the 10ml mark using deionized or distilled water. This is where most people make the mistake. You can not use tap water or tank water for this step. Also do not use RODI water unless it matches the readings of distilled. If your RODI water has solids in it, you might get inaccurate results. Once the deionized or distilled water and reagent A are combined, invert the cuvette 5 times to mix.

Step 4. Make sure the cuvette is completely clean of any fingerprints or oils. Use a microfiber cloth to wipe it down. Place the cuvette into the tester, close the lid (make sure it is completely closed for an accurate reading).

Step 5. Press the button. When the screen shows ADD C2, open the lid and remove the cuvette from the tester.

Step 6. Using the 0.1 ml pipette, add 0.1 ml of sample water. You should use the pipette tip for more accuracy. Push the button to the first “stop”. You will notice there are 2 stop points with this pipette. Then immerse the pipette into the sample. Release the button slowly to the original position. Add the sample into the cuvette by pushing the button to the second “stop”.

Step 7. Add 1 packet of reagent B to the sample. Then cap the cuvette and shake for 15 seconds. Then wait 15 seconds for the bubbles to dissipate.

Step 8. Again wipe the cuvette with a microfiber cloth to remove any fingerprints or oils. Insert the cuvette back into the tester and press the button. The LCD screen will show you the correct concentration of calcium in ppm.

Following these 8 steps will ensure you get an accurate reading every time.

Analyzing The Results


Hanna Instruments Calcium checker shows accuracy @ 25°C/77°F is ±6% of reading, which is highly accurate.

The normal calcium levels for a saltwater tank is between 380-450ppm. Adjust your dosing schedule as necessary to stay within this range. The Hanna checker will give you results from 200-600ppm.

A few important notes about using the Hanna Calcium test kit. You have to make sure the cuvette is clean and free of any residue on the inside and also free of fingerprints and smudges on the outside. This can affect the path between the LED and light detector and may show inaccurate test results.

One of the great things about the Hanna checkers is by using an actual electronic microchip machine, we can eliminate human error by misreading color charts and graphs. Other hobby test kits can be easy to use but reading the results can be difficult.

The problem with misreading the results especially on color charts is the fact we will make changes to aquarium water that are not necessary causing more harm than good.


Should You Buy The Hanna Calcium Checker?


Yes, you should! Here is why.

In my opinion, the Hanna test kits are a very reliable and accurate way to check all your aquarium water parameters. They are my number one recommended testers on the market today.

It will allow you to make the necessary adjustments for your tank keeping your corals healthy and vibrant.

Also, they are affordable and provide great value. Not only is the quality great, but you will be able to complete 25 tests initially with the kit. You will pay more upfront for this tester compared to other test kits.

For example, you might pay $50 for the Hanna kit for 25 tests and only $20 for another brand like Seachem or Salifert and get 75-100 tests.

But the value comes in when you need to buy replacement reagents. Once your 25 tests are used up, you can buy replacement reagents for $8-10. With other brands, you most likely need to buy another full kit. So the upfront cost is more, but that will balance out and you will be on the plus side and saving money in the long run.

Also, consider the quality of the test kits. The Hanna checkers are superior to others and in my opinion well worth the initial cost. I have used most of the other brands on the market, and while some do a great job, they just can’t compare to the Hanna test kits.

I am more than happy to pay a bit more for accurate testing.


You can check today’s price of the Hanna Alkalinity checker on Marine Depot here.

If you would like to download a copy of the manual, you can do that here.