Nutrients such as Phosphate, Ammonia, Nitrite and Nitrate are central in many environmental processes within the marine environment, including several microbial, plant and animal metabolic processes. The Phosphate Analyser was developed as part of the COMMON SENSE FP7 project (614155). The analyser is based on a combination of microfluidic analytical systems, colorimetric reagent chemistry, low-cost LED-based optical detection, low cost pumps and wireless communications.