EC Sensor Design HELP

Hello!

I was trying to gather some resources on designing an EC sensor that for instance, I could connect to an Arduino board.

I saw many people on YouTube just using two electrodes and some wires and simply connect them to analog pins of the Arduino board. I do not have much knowledge in electronics but it seems to me that this way of building such a sensor is very unreliable and probably requires that you calibrate the sensor quite often.

I understand the principle behind measuring EC: basically measuring the resistance between the two electrodes.

However, I was wondering if there's a "better" way to design such a sensor. I could not find many sources online myself, perhaps anyone who could help me out here?

A schematic would already help.

Thanks a lot!

What is it that you want to measure ?

If there is water or not ?
The soil humidity ?
The soil salinity ?
The PH value of the soil ?

Or do you really want to measure the electrical resistance of the soil ? Is the sensor always submersed ? There are many schematics for that online. The Arduino has a very high input impedance, so it is indeed possible to use that. The problem is the oxidation of the probes because of the voltage on it.
For a reliable measurement with a sensor that is always in the water, I would use a galvanic separated sensor.