Conductance meters check the electrical conductivity of liquids, particularly water-based solutions. This is a way to check the purity of water. In technical applications, for example, demineralised water with particularly low conductivity is used in coolant circuits, and it is used in laboratories as a solvent. These devices are also used in fishkeeping, fish farming and water monitoring to guarantee consistently high water quality. For this reason most devices are watertight and particularly sturdy. Measurement results can be saved for later evaluation.