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Adam OsborneSep 18, 2025
Why does my Hach Measuring Instruments show a red LED and measure hard water?
- KKyle GraySep 18, 2025
If the red LED is continuously on and the Hach Measuring Instruments measures hard water, make sure to set the flow rate to 200 mL/minute. The issue could be caused by a flow that is too low, preventing the sample cell from completely flushing out the color, or a flow that is too high, causing the water to bypass the pinch block and dilute the color.















