The HI93750-01 are high quality reagents that are pre-measured, allowing for users to achieve fast and accurate colorimetric measurements. These reagents follow an adaptation of the Tetraphenylborate method. The reaction between potassium and reagents causes a turbidity in the sample. By simply adding the reagents to the sample, a reaction will take place and a compatible benchtop or portable meter can be used to determine the concentration. The results will be displayed in mg/L (ppm) of potassium. Based on the range selected with the meter these reagents are designed to be used with samples that have an expected concentration between 0.0 and 200 mg/L potassium for benchtop photometers and 0.0 and 100 mg/L potassium for the portable photometer. Each meter offers multiple ranges.