Capacitance level gauges can only be used in connection with the liquid they are inteded for. Using them on other liquids, with different dielectric properties, will give errors in the reading with unexpected results, including vessel overfill.
Generally, capacitance should be seen as a last-resort technique for measuring level, as the slightest change in liquid properties can have a vast impace on the operation of the device.
It might be easier to go radar instead. It will certainly be less hassle.
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