The HANNA HI758 marine calcium pocket checker is a digital colorimeter designed to perform calcium tests. The HI758 marine calcium checker comes supplied with: 2 cuvettes with caps, 100 µL pipette, syringe, plastic pipette, reagents for 25 tests, battery, instructions, and quick start guide.

Accurate and simple measurements, direct on-screen display of calcium levels in marine water.

Always get accurate results for your saltwater aquarium with our portable digital meter.
Our marine calcium colorimeter is the perfect alternative to traditional visual test kits. These kits have limited accuracy because they rely on the human eye to match colors. Our handheld colorimeter eliminates this issue by providing a direct calcium reading in ppm of CaCO₃.

This portable colorimeter fits in the palm of your hand and can easily be carried in your pocket. With one-button operation, you can quickly get results without any hassle.

The term “water hardness” refers to the amount of dissolved calcium and magnesium salts in the water. These minerals come from limestone rock formations and are commonly found to varying degrees in most natural waters. Water is often considered “hard” when it contains more than 120 mg/L of CaCO₃.

Calcium is essential for plant nutrition and is a vital component of bones, shells, and plants. In water, calcium as carbonate is one of the main contributors to water hardness.

The HI758 calcium checker is very easy to use. You’ll get test results by following these 3 simple steps:
Step 1: Prepare the sample as described in the manual.
Step 2: Insert the zero cuvette into the checker and hold the button for 3 seconds to start the reaction timer. The meter will automatically zero.
Step 3: Remove the zero cuvette, insert the sample, and press the button to take the measurement.

HANNA Checkers
HANNA checkers are small, portable, and most importantly, provide much more precise results than standard chemical test kits. Featuring advanced technology and a simple design, they allow for easy, hassle-free measurements.

These digital photometers bridge the gap between basic test kits and professional instruments such as calibratable photometers.

Conventional test kits are not very accurate and rely entirely on the user visually interpreting color, which is why HANNA has digitized the measurement and developed a truly accurate pocket-sized digital colorimeter.

The Checker® is both precise and highly affordable.
Its ergonomic design fits in the palm of your hand or your pocket. The easy-to-read LCD screen and auto-off function ensure battery life is preserved if you forget to turn it off.

Easier to use and more precise than visual test kits:

• High precision

• Large, easy-to-read digits

• Auto shut-off

Dedicated to a single parameter:

• Designed to work with Hanna reagents

• Uses 10 ml glass cuvettes