Isodaq Technology is now part of Hydro International.

Aqua TROLL 400


  • Multi paramater water quality sonde
  • Telemetry links - Modbus, RS485 and SDI12 
  • Groundwater and surface-water applications
  • EC, TDS, DO, ORP, pH, T and depth
  • Titanium housing is suitable for harsh environments


Full Description

Ideal for continuous water quality monitoring, the Aqua TROLL 400 Multiparameter Instrument easily connects to existing telemetry systems, data loggers, and samplers. Use the probe in fresh, marine, contaminated, and process waters.

The compact instrument houses six water quality sensors and measures 12 parameters:

  • Actual and specific conductivity, salinity, total dissolved solids, resistivity, and density
  • Dissolved oxygen
  • ORP
  • pH
  • Temperature
  • Water level and water pressure (absolute) 


  • Coastal deployments
  • Long-term surface-water monitoring
  • Long-term groundwater monitoring
  • Mining
  • Real-time monitoring networks
  • Remediation
  • Stormwater management

Confidence in Your Data

  • Field-tested sensor technologies lower your total cost of ownership by providing stable, accurate results.
  • Sensors are factory calibrated with NIST®-traceable standards (where applicable).
  • DO readings are automatically compensated for salinity. 
  • DO and level readings are automatically compensated for barometric pressure.
  • The RDO Sensor includes integrated health diagnostics. 

Greater Efficiency & Flexibility

  • Easy installation reduces errors and training time, while increasing productivity.
  • With open communication protocols, the instrument easily interfaces with your current system. Access data anytime with a radio, controller, data logger, sampler, telemetry system, or SCADA/PLC system.
  • Long-lasting calibrations reduce site visits.