Salinity Sensor

What is Salinity?

Salinity is the measure of the concentration of dissolved salts in water. Salinity is measured indirectly by testing the electrical conductivity (EC) of the water. Saltwater conducts more electricity than water with no dissolved salt. Fresh water has almost no dissolved salt, whereas ocean water has a salinity in the range of around 34 to 36 parts per thousand (ppt). Brackish water is a mixture of fresh and saltwater.

Aquaread Salinity Sensor.

Aquaread’s salinity measurement is calculated within our software using the electrical conductivity (EC) measurement, temperature measurement and various other constants in a complex equation.

We output the salinity measurement in practical salinity units (PSU) and have the option to change this to PPT (parts per thousand) within the menu options.


Key Features

  • Calculated parameter that’s always included on every Aquaprobe and Aquasonde.
  • Uses the Corrosion resistant gold coated stainless-steel EC sensor.
  • Measurement range 0 – 70 PSU.
  • Resolution 0.01 PSU.
  • Accuracy of 1% of reading.
  • Requires no calibration – this is taken care of when you calibrate the EC sensor.

Our salinity sensors come as standard on many of our probes, below are some examples.

To see all of the probes that feature SAL please visit the Products section.



Portable, GPS AquaPlus Optical DO/EC system



Advanced portable multi-parameter Aquaprobe.


LeveLine CTD

Adds conductivity and salinity measurements

Always included

The salinity parameter is included on every Aquaprobe and Aquasonde, it is also included in the AquaPlus optical dissolved oxygen sensor and our Leveline-CTD water level and conductivity logger.