Effectively monitoring hydrogen peroxide online in salmon farms

Importance of the Topic

The rapid expansion of salmon farming has increased the risk of lice infestations in confined net cages. Hydrogen peroxide (H2O2) baths are a widely used delousing treatment, but maintaining the correct concentration is crucial. Overdosing can lead to oxidative stress, skin damage, or fish mortality, while underdosing may be ineffective against parasites. Online monitoring of H2O2 ensures safe, efficient treatment and supports sustainable aquaculture practices.

Study Objectives and Overview

This application note describes an online analytical approach for measuring H2O2 concentration in salmon delousing baths. The primary goals are to demonstrate rapid, reliable titrimetric analysis using the Metrohm Process Analytics 2060 TI Process Analyzer and to highlight its benefits over manual methods.

Methodology and Instrumentation

The H2O2 concentration is determined by dynamic endpoint titration (DET) with cerium(IV) as titrant. A platinum ring electrode serves as the indicator, paired with an Ag/AgCl/KCl reference electrode to detect the redox endpoint. The system automatically draws samples, performs titration, and calculates concentrations in under two minutes per analysis.

Main Results and Discussion

• The analyzer quantifies H2O2 in the 0–2500 g/L range, covering typical treatment bath levels.
• Average analysis time is below two minutes, enabling frequent measurements and real-time adjustments.
• Continuous monitoring minimizes the risk of harmful concentration spikes or dips.
• Automated titrations reduce labor and human error compared to manual sampling and laboratory titrations.

Benefits and Practical Applications

• Rapid detection of dosing errors and bath upsets
• Improved fish health through precise concentration control
• Higher operational efficiency by monitoring multiple baths (up to 10) with a single analyzer
• Reduced chemical consumption and waste

Future Trends and Opportunities

Integration of online analyzers with farm control systems will enable fully automated dosing feedback loops. Expanding analyte panels (alkalinity, hardness, peroxide derivatives) can further optimize water quality management. Advances in remote data access and AI-driven process analytics will support predictive maintenance and proactive treatment strategies in aquaculture.

Conclusion

The Metrohm 2060 TI Process Analyzer provides fast, accurate online H2O2 monitoring for salmon delousing baths. It enhances treatment safety, reduces manual workload, and supports sustainable salmon farming by ensuring correct peroxide dosing at all times.

Used Instrumentation

• 2060 TI Process Analyzer (Metrohm Process Analytics)
• Platinum ring indicator electrode
• Ag/AgCl/KCl reference electrode
• Dynamic endpoint titration (DET) module

References

1. Salmon Farming Industry Handbook 2021; Mowi Industry, 2021.