Submersible Water Quality Sensor-Transmitters

The pHionics STs Series™ simplifies your water quality measurements with durable, noise-resistant, and easy-to-use instruments for temperature, pH, conductivity, dissolved oxygen, or ORP (redox).

pHionics STs Series pH Sensor/Transmitter


+ Temperature

STs Series Conductivity Water Quality Sensor and Transmitter


+ Temperature

STs Series Dissolved Oxygen Water Quality Sensor and Transmitter

Dissolved Oxygen

+ Temperature

STs Series ORP Water Quality Sensor and Transmitter

ORP (redox)

+ Temperature

pHionics STs Series pH Sensor and 4-20mA transmitter in use

The pHionics STs Series™ combines the sensor and transmitter into a highly accurate, durable, compact device to simplify water quality measurement.

Simple Setup

  • Five minute setup out of the box
  • Reversible input protection to prevent improper wiring
  • Fewer cables and wires than traditionally separated systems

Simple Maintenance

  • Fully replaceable parts requiring no special tools
  • Detailed tutorials provided through our YouTube Channel
  • Removable electrode guard for easy cleaning

Simply Accurate

  • Kevlar-reinforced, shielded cable for accurate signal transmission
  • Differential amplifier to remove background noise
  • Input-output isolation to eliminate ground loops
Water Quality Sensor and 4-20 ma Transmitter

See how simple your life* can be with pHionics

*pH, conductivity, dissolved oxygen, ORP, or temperature measurement-wise.  We can provide relationship advice as well but that doesn’t come with our two year warranty.