The density is a measure of the correct salt content and is thus the most important water value in the sea water. Marine creatures react highly sensitively to lower or higher salt levels and brief fluctuations in density.
- Grip the tip of the dry and clean densimeter with dry fingers and submerge in the water until it floats on its own.
- The densimeter must float freely.
- There must be no air bubbles on the densimeter, as these will falsify the reading.
- Read the value from the scale at the level of the water surface (not at the level of the water which is "climbing" up the densimeter above the surface level).