The manufacturer informs: 

The Hanna Sea Water Alkalinity Checker measures alkalinity in dKH and uses a fixed wavelength LED source and a silicon photocell to provide the accuracy of professional instrumentation at the affordable price of a chemical test kit.

he Hanna Checker for Alkalinity in seawater (dKH) represents a good compromise between the choice of simple chemical test kits and professional instrumentation. Chemical test kits have limited accuracy and resolution because they are based on the distinction of colour differences perceived by the human eye. Professional-type instrumentation integrates a light source consisting of an LED or tungsten lamp with a filter and a light detector to accurately determine absorbance and ion concentration. Professional instruments offer higher resolution and precision, but can cost hundreds of euros. The Checker^® Hanna for Alkalinity in Seawater measures alkalinity in dKH and uses a fixed wavelength LED source and a silicon photocell to provide the accuracy of professional instrumentation at the affordable price of a chemical test kit.

The Checker HC (portable chroma meter) HI772 is a simple, accurate and convenient instrument for measuring alkalinity in degrees of calcium hardness, commonly abbreviated as dKH. Alkalinity is one of the most important parameters to monitor in marine aquaria. It helps maintain a stable pH, which is essential for most aquatic life. In seawater, carbonates and bicarbonates determine alkalinity and are critical for coral health. Designed as a more accurate alternative to chemical test kits, the HI772 provides fast and accurate results in four simple steps:

Main features:

• Easier to use and more accurate than chemical test kits
• Dedicated to a single parameter
• Small size, great convenience
• Ideal for: Aquaculture and Aquariums, Water Quality