Hanna Instruments Freshwater Alkalinity Checker HC (0–500 ppm) (HI775)

Hanna Instruments Freshwater Alkalinity Checker HC (0–500 ppm)

The Hanna Instruments HI775 Checker® HC is a pocket-sized handheld colorimeter designed to measure total alkalinity in drinking water and freshwater systems with a range of 0 to 500 ppm (mg/L as CaCO3). It bridges the gap between basic chemical test kits and professional laboratory instruments, delivering digital results in four simple steps — no subjective colour-chart comparisons required. The meter complies with UNE-ISO 17381:2012 and comes ready to use straight out of the box.

How it works

The HI775 uses a fixed-wavelength LED light source (610 nm) paired with a silicon photocell detector to analyse the colour change produced by the included alkalinity reagent. Simply zero the meter with an unreacted sample, add the reagent to the cuvette, reinsert it, and press the button — the alkalinity value appears directly on the digital display in seconds. The built-in auto-off function cuts power after ten minutes of inactivity to preserve battery life. Each unit ships with two cuvettes with caps, reagent for 25 tests, a syringe with tip, one AAA battery, and a quick-start guide.

Compatibility & reagents

The HI775 is calibrated for freshwater and drinking water alkalinity testing — it is not intended for saltwater or marine applications. Replacement reagent kits (HI775-26, 25 tests per pack) are required for ongoing use and are sold separately. Important: if the water sample contains chlorine, one drop of chlorine-remover reagent HI93755-53 must be added to the unreacted sample before zeroing the meter to avoid interference with the reading.

Why genuine matters

Genuine Hanna Instruments Checker® HC units are factory-calibrated and engineered to work exclusively with Hanna’s own reagent chemistry.