Hanna pH Checker

It has been a long time since Hanna released a new device that can be used by those of us in the Saltwater Aquarium community, but Hanna has announced a new Hanna Marine pH Checker HC (Handheld Colorimeter HI780) to be released this month. I was excited when I heard that Hanna was releasing this new device; I couldn’t wait! I’m very familiar with Hanna products, so I offered to test one of the sample units that were sent to Marine Depot. I currently use the Hanna pH Plus Checker to validate the pH readings from my Aquarium Controller and to check the pH of my freshly mixed saltwater when doing water changes. Luckily, I was offered a sample Hanna Marine pH checker HC to take home and had fun using it with my 29 gallon reef aquarium.

HI780 Checker

The first thing I noticed with this new device was its packaging; they maintained the same design as the other popular Hanna Colorimeters such as the Alkalinity and Phosphate checkers – the classic black protective plastic case to store the components and the traditional sleeve showing a graphic design of the device found inside. This one came with a clear wrapping material protecting the sleeve. Unboxing the Hanna ph Marine Checker HC revealed the black storage case, the pH checker itself, one AAA battery, two glass cuvettes, a 30ml reagent bottle, and the instruction manual.

This colorimeter is the same shape and size as all the other Hanna handheld colorimeters, but each one has its own given color to help you differentiate them if you own all the Hanna colorimeters. If you’re familiar with the other colorimeters made by Hanna, you will find using this new Hanna Marine pH Checker HC to be a breeze. I compared this colorimeter to the simple-to-use Hanna Saltwater Aquarium Alkalinity Colorimeter Checker HC, and the instructions are nearly identical.

pH Checker parts

Hanna recommends rinsing the glass cuvettes with RODI or distilled water and gently drying them with a lint-free paper towel before testing. A lint-free microfiber cloth intended for eyeglasses works great for wiping these cuvettes. It is important for the cuvette to be free of lint, dust, or oils from your fingers, as that could interfere with the test results.

Before you begin, install the AAA Battery. There is a small screw on the underside of the checker securing the battery door. You’ll need a Philips head screwdriver for the screw, and if you’re having trouble popping the door open, you may carefully pry it open with a fingernail or small flathead screwdriver. Once the battery is installed, the fun begins.

  • Step #1 -Press the on/off button to turn the device on; “Add C1” with “Press” will appear blinking on the screen.
  • Step #2 - Fill one of the cuvettes to the 10ml line, replace the cap, and insert it into the checker.
  • Step #3 - Press the on/off once and wait for “Add C2” to appear on the screen.
  • Step #4 - Remove the cuvette from the checker, open the cap, add 5 Drops of the provided reagent, and gently swirl the cuvette for the liquids to mix properly.
  • Step #5 - Insert the cuvette back into the checker, close the checker’s cap, and press the on/off button once. You will see the pH reading on the display within a couple seconds.

Hanna Checker Cuvet

After comparing this Hanna Marine pH Checker HC with my Hanna Checker Plus pH Tester, I immediately realized there are benefits to using this new colorimeter instead. The new Marine pH Checker HC does not require a storage solution like the Checker Plus pH Tester does. You simply need to rinse the cuvettes after each use. The Checker Plus pH Tester requires frequent calibration, but the new Marine pH Checker HC does not.

While researching, I noticed there is a “Calibration Set” available for purchase separately, and I was curious. I decided to call Hanna Instruments to ask about it, and I was advised that It is not required to calibrate this colorimeter. The Hanna Marine pH Checker HC comes pre-calibrated out of the box, and there is no need to re-calibrate it. Hanna explained that since these are scientific instruments, the Calibration Set is a “validation step” which is sometimes required in certain professional laboratory settings. These Calibration sets are also available for all their other colorimeters. I will most likely be ordering the Calibration Set to validate the calibration occasionally just to have the peace of mind that my unit is always accurate.

I compared the readings of the pH Marine Checker HC with my pH Checker Plus and the pH readings of my recently calibrated pH controller. The pH reading of my controller was 7.75 which is right within the accuracy expectation of +/- 0.2 pH. The pH Checker Plus was inaccurate with a reading of 7.46 pH which indicates that it may need to be calibrated. Overall, I am very satisfied with the Hanna pH Marine Colorimeter Checker and can’t wait for the highly anticipated Hanna Nitrate Marine Colorimeter Checker HC (coming soon).