The HI93755-01 are high quality reagents that are pre-mixed, allowing for users to achieve fast and accurate colorimetric measurements. These reagents follow a colorimetric method in which the reaction between alkalinity in a water sample and the reagent causes a green tint to be produced. By simply adding 1.0 mL of the HI93755-01 reagent to the sample, the reaction will take place and a compatible photometer can be used to determine the concentration from the color that is produced. The results will be displayed in mg/L (ppm) of alkalinity as calcium carbonate (CaCO3). These reagents are designed to be used with samples that have an expected range of 0 to 500 mg/L calcium carbonate.