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Phosphate Probe

Real-time, high-frequency, lab-quality phosphate monitoring.

Image of DropletSens Probe


  • Based on established Molybdenum Blue test
  • Dissolved (ortho-)phosphate determined autonomously
  • Fully quantitative
  • On-device standard for performance QC



0 - 8 mg/L PO4-P
Detection Limit
0.01 mg/L PO4-P
Measurement Frequency
up to every 10 seconds
default setting is every 15 min


Temperature range
0 - 35 °C
Maximum deployment depth
1 m
Power consumption*
* for continuous use measuring every 15 min
1.5 W


400 mm
150 mm
8.2 kg


RS232/RS485, Modbus, Bluetooth, SCADA compatible
Data output
Remote streaming

Specifications PDF


  • Reagent change after 3 months if in continuous use
  • Required inlet filter change frequency depends on application; typically 3 months for environmental applications (turbidity ≤250 NTU)


Process Control, Rivers, Streams & Lakes, Coastal, Agriculture, Aquaculture, Industrial, Environmental Monitoring, Estuary Monitoring, Catchment Monitoring, Effluent Monitoring, Nutrient Mapping, Nutrient Recovery, Nutrient Trading, Nature-Based Solutions Effectiveness Monitoring.

Nanodroplet microfludic approach for DropletSens™ platform - compact liquid reagent based sensors.

Why phosphate?

Phosphate is monitored in the water network and watercourses to better understand and reduce the environmental impact caused by sewage treatment outflows, storm overflows and agricultural run-offs, which can result in excessive algal growth and fish deaths. This pollution data can be used to guide investment decisions, monitor effectiveness of remedial measures such as wetlands, and support nutrient-trading schemes to unlock housing developments.

Apart from the dissolved ‘reactive phosphorus’ or ‘ortho-phosphate’ which DropletSens™ measures colorimetrically, there is also suspended or bound phosphorus, with all phosphorus compounds together adding up to ‘Total Phosphorus’ or ‘Total-P’. At present there are no electrochemical or spectral approaches that can measure ortho-phosphate.

Phosphate discharge limits are in place in most countries to protect the receiving ecosystems. Increasing focus is also placed on Phosphorus recovery, as it is a limited resource and required for fertilizer production.

Photo of a bridge over water
Photo of people with clipboards wearing hardhats

Monitoring Solutions

We offer the following solutions for monitoring phosphate:

A. SWS turn-key solution: fully autonomous SWS sensor probes with own battery, connectivity and user interface:
SWS turn-key solution diagram

B. Third party static, floatable & moveable integrated solutions.

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If you are interested in our products or have monitoring needs not currently covered, please contact us.