Nitrate monitoring is the process of measuring nitrate (NO₃⁻) concentrations in water to ensure it remains safe, compliant, and environmentally responsible. Elevated nitrate levels, often caused by agricultural runoff, wastewater discharge, or industrial pollution, pose serious risks, including eutrophication, groundwater contamination, and public health issues. Accurate, real-time nitrate detection is essential for protecting drinking water, optimising wastewater treatment, and environmental monitoring. The TriOS NICO UV-absorption sensor is the industry’s preferred choice for continuous, reagent-free nitrate monitoring, combining high sensitivity, turbidity compensation, and low maintenance in a compact, durable design.
The NICO is a leading nitrate sensor for real-time nitrate detection and monitoring in wastewater treatment, drinking water, and environmental applications. Using UV-absorption technology, the NICO provides precise, reagent-free measurements of NO₃-N (nitrate) while compensating for turbidity to ensure highly accurate readings. This in-situ nitrate monitoring sensor is designed for continuous water quality analysis, delivering reliable data even in challenging water conditions.
Engineered for continuous water quality monitoring, the NICO sensor eliminates the need for chemical reagents, making it a cost-effective and environmentally friendly solution. Its robust stainless steel or titanium housing ensures durability in wastewater treatment plants, drinking water facilities, and industrial water processing systems.
Find out more about the NICO sensor by downloading our comprehensive datasheet. This detailed document provides in-depth information on specifications, features, and applications, empowering you to make informed decisions for your water quality monitoring needs.
Nitrate monitoring is crucial for wastewater treatment, drinking water, and environmental applications, ensuring compliance and process efficiency. The TriOS NICO is a UV-absorption sensor that provides real-time, reagent-free nitrate (NO₃-N) detection with advanced turbidity compensation, eliminating interference from suspended solids. Built for continuous water quality monitoring, NICO delivers high-precision, low-maintenance performance in a robust, IP68-rated stainless steel or titanium housing. It is designed for seamless integration and supports Modbus RTU, RS-485, and Ethernet TCP/IP, making it ideal for automated water quality systems.

Proven UV-Absorption Technology – Delivers precise, reagent-free nitrate detection
Cutting edge Turbidity Compensation – Eliminates interference from suspended solids
Multi-Path Optical System – Configurable optical path lengths from 0.3 mm to 50 mm
Fast & Stable Readings – T100 response time of 20 seconds for real-time monitoring
Integrated Data Logger – 2 GB storage for long-term measurement recording
Seamless Digital Integration – Compatible with Modbus RTU, RS-485, and Ethernet TCP/IP
Low Maintenance & Calibration Needs – Calibration interval up to 24 months
Robust Construction – IP68-rated stainless steel or titanium housing for extreme environments
Wastewater Treatment Plants – Real-time nitrate monitoring for process optimisation
Drinking Water Safety – Ensure regulatory compliance for potable water supplies
Environmental Monitoring – Track nitrogen pollution in lakes, rivers, and reservoirs
Industrial Process Water – Maintain water quality in food, beverage, and chemical industries
Measurement Range: 0.05 – 60 mg/L (varies by optical path length)
Turbidity Compensation: Eliminates interference from suspended solids for accurate readings
Response Time: Fast T100 response time of
Data Logging: 2 GB internal memory for long-term measurement storage
Housing Material: IP68-rated stainless steel or titanium for durability in harsh environments
Integration & Connectivity: Supports Modbus RTU, RS-485, and Ethernet TCP/IP for seamless system integration
Low Maintenance: Calibration interval up to 24 months, with maintenance typically ≤0.5 h/month
Power & Pressure Ratings: Operates at 12–24 VDC (±10%) with max pressure of 30 bar (SubConn) / 3 bar (fixed cable)
The NICO is the best solution for real-time nitrate monitoring, providing accurate, reagent-free measurements with advanced UV-absorption technology. Designed for wastewater treatment, drinking water safety, and environmental monitoring, the NICO sensor delivers precise nitrate (NO₃-N) detection with automatic turbidity compensation to eliminate interference. Its low-maintenance design, extended calibration intervals, and seamless Modbus RTU and Ethernet integration make it the ideal choice for continuous monitoring in demanding applications.
With robust stainless steel or titanium housing and an IP68-rated waterproof design, the NICO is built for harsh environments, ensuring durability and long-term performance. Whether optimising nitrogen removal in treatment plants or ensuring compliance in drinking water systems, the NICO sensor provides unmatched accuracy, efficiency, and reliability.

South East Water has chosen the TriOS NICO nitrate sensor to enhance real-time borehole monitoring. This sensor ensures accurate and reliable nitrite detection using UV-absorption technology. With reagent-free operation, advanced turbidity compensation, and seamless integration, the NICO provides a cost-effective, low-maintenance solution for protecting drinking water quality.
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Looking for a reliable nitrite sensor? The NICO delivers real-time, reagent-free nitrate and nitrate monitoring with advanced UV-absorption technology. Whether for wastewater treatment, drinking water monitoring, or industrial applications, our experts at PMA Ltd are here to help you find the perfect solution.

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