The handheld Checker meters HI755, HI772, and HI775 are digital colorimeters designed to test alkalinity.

• Accurate and easy measurements
• Direct on-screen display of alkalinity values
• Depending on the range and water type:
 Range: 0 to 300 ppm; Water type: marine (HI755)
 Range: 0.0 to 20.0 dKH; Water type: marine (HI772)
 Range: 0 to 500 ppm; Water type: drinking water (HI775)

Water alkalinity is one of the most important parameters to measure in aquariums, as it helps maintain a stable pH—a crucial factor for most aquatic life.

Water alkalinity can be defined as a measure of its ability to neutralize acids. In natural waters, this property is mainly due to the presence of certain salts of weak acids, although weak and strong bases can also contribute. These substances act as buffers to resist the pH drop that results from the addition of acids. This concept is widely used in wastewater treatment practices.

The concentrations of certain species (hydroxides, carbonates, and bicarbonates) create a buffering effect in water by absorbing protons, helping maintain a stable pH. This is essential for living organisms and for specific systems such as blood flow.

It is also important to note that waters with high alkalinity are not necessarily harmful for human consumption—for example, carbonate-rich water, also known as soda water.

Our alkalinity colorimeters make it easy to trust your measurements. You no longer need to struggle to match colors—our portable meter eliminates the need for a color chart by providing a direct digital reading of alkalinity.

Our Checkers fit in the palm of your hand and can be easily carried in your pocket. With single-button operation, they allow for quick and simple alkalinity testing.

Alkalinity test results can be obtained in four simple steps:

Step 1: Add a sample to the cuvette (included).
Step 2: Insert the sample into the Checker and press the button to zero the instrument.
Step 3: Remove the sample and add the reagent as indicated in the manual.
Step 4: Reinsert the sample and press the button for 3 seconds to measure the result.

HANNA Checkers are small, portable, and most importantly, provide more accurate results than typical chemical test kits. With improved technology and a simple design, they make measurements easy and hassle-free.

These digital photometers or test kits serve as a bridge between basic test kits and professional instrumentation like a calibratable photometer.

Conventional test kits are not precise and rely entirely on the user's perception of color, which is why HANNA has digitized this measurement and developed a highly accurate pocket-sized digital colorimeter.

The innovative design of the Checker fits in the palm of your hand or your pocket. The LCD screen is easy to read, with an automatic shut-off function in case you forget to turn it off.

• High accuracy

• Large, easy-to-read digits

• Automatic shut-off

• Designed to work with Hanna reagents

• Uses 10 ml glass cuvettes