Water Quality Measurement, Testing and Analysis Categories: 4 - 20 mA Water Quality Sensors Environmental and Industrial Water Quality Sensors & Data Loggers Multiparameter Water Quality Sondes Continuous Online Water Quality Monitoring Pocket Water Testers LAB & FIELD INSTRUMENTS Field Water Quality Meters Benchtop Meters BOD & Respirometers Continuous Online Water Quality Monitoring 4 - 20 mA Water Quality Sensors Environmental and Industrial Water Quality Sensors & Data Loggers Multiparameter Water Quality Sondes Continuous Online Water Quality Monitoring Pocket Water Testers LAB & FIELD INSTRUMENTS TB500 Online Turbidity Analyzer (product no longer available) from $1,962.00 WTW PhotoFlex Portable Colorimeter from $2,024.00 MTOL+ Online Process Turbidimeter $0.00 HF Scientific CLX OnLine Residual Chlorine Analyzer $0.00