Measure nutrients, salts, and other dissolved solids. As your membranes age, the TDS (total dissolved solids) of the product water will gradually increase. A hydrotester will measure the water quality in terms of how much salt is being removed. It is common to want to change membranes when the system gets to about 750-800ppm (parts per million) of TDS.

• Four modes: EC: mS, uS, TDS: ppt, ppm.
• Fast and accurate, +/-2%
• Simple to use
• Digital calibration
• Water resistant
• Durable
• Auto shut off after five minutes
• EC to TDS conversion factor: NaCl (0.5 avg)
• Auto temperature compensation (ATC)
• Hold function
• Power: 3 x 1.5V (357A)
• Battery life: approximately 2 years
• Dimensions: Length 153mm (6.0″), Width 32mm (1.3″), Height 18mm (0.7″)
• Weight: 53.9g (1.9oz)