SeaFET pH Ocean Sensor

SeaFET™ Ocean pH Sensor

The SeaFET™ Ocean pH sensor is an ion selective field effect transistor (ISFET) type sensor for accurate long-term pH measurements in salt water.

NOTE: Newer firmware is now available here. [SeaFET Firmware v3.6.4 - November 2016]

The SeaFET™ reports pH determined potentiometrically in two different ways.  The ISFET potential is measured against a reference electrode bearing a liquid junction (internal reference) and against a solid state reference electrode without a liquid junction (external reference).  This approach provides the user with the ability to quality assess instrument performance and ultimately achieve a greater understanding of the state of acid/base equilibria in seawater.

The SeaFET™ Ocean pH sensor has been used extensively for:

  • ocean acidification research
  • coral reef research
  • coastal marine biology
  • environmental monitoring.

The SeaFET™ Ocean pH Sensor was developed by Dr. Kenneth Johnson of the Monterey Bay Aquarium Research Institute (MBARI) and Dr. Todd Martz of the Scripps Institution of Oceanography, University of California San Diego.  We collaborated with MBARI and Scripps to make the instrument commercially available to the research community. SeaFET™ sensors have now been deployed in many locations, including Canada, USA, France, UK, Australia and China.

The sensing element of the SeaFET™ is an ion sensitive field effect transistor (ISFET).  This class of device has been used for pH sensing in industrial processes, food processing, clinical analysis and environmental monitoring. The advantages of the ISFET include robustness, stability and precision that make it suitable for ocean pH measurement at low pressure.

Replacing a SeaFET™ Ocean pH Sensor Battery (Note this is an older model)

Click on the Image to Watch the Video