The Hanna Marine Calcium Checker® bridges the gap between simple chemical test kits and professional instrumentation. Chemical test kits have limited accuracy and resolution since they rely upon the human eye to discern differences in color. Professional instrumentation incorporates a light source such as an LED or tungsten lamp with a filter and a light sensing detector to precisely determine absorbance and ion concentration. Professional instrumentation offers greater resolution and accuracy but can cost hundreds of dollars. The Hanna Marine Calcium Checker® uses a fixed wavelength LED and silicon photo detector to provide the accuracy of professional instrumentation at the affordable price of a chemical test kit.

The HI758 Checker® HC (Handheld Colorimeter) provides a simple, accurate and cost-effective way to measure calcium. Required for the development of calcium carbonate skeletons of coral reefs, calcium is a crucial component of marine waters. Designed as a more accurate alternative to chemical test kits, the HI758 provides quick, accurate results.