Hach's SL250 Portable Parallel Analyzer (PPA) is an innovative multiparameter water quality meter that allows you to simultaneously perform colorimetric and probe-based measurements. The instrument and corresponding Chemkey reagents are easy to use regardless of technical expertise. Compared to traditional powder or liquid reagent methods, Chemkeys use a simplified testing method that requires no sample preparation, making the process significantly easier, faster, and safer while drastically reducing variability in results. Colorimetric tests include free chlorine, total chlorine, fluoride, high range manganese, zinc, copper, nitrite, dissolved iron, high and low range alkalinity, high and low range orthophosphate, high and low range hardness, peracetic acid, and more. Probe-based tests include pH, dissolved oxygen, conductivity, and more. *Not suitable for chloramination applications*