Corrosion Resistant Soil Moisture Sensor

Is anyone else using this soil moisture sensor for Arduino Moisture Sensor Soil Hygrometer Humidity Detection Module for sale online | eBay? It claims to be corrosion resistant. Does anyone know what material are the probe tips made of? I can't seem to figure it out, it doesn't seem to be metallic. Is it really possible for this to be corrosion resistant?

Byork:
Is anyone else using this soil moisture sensor for Arduino Moisture Sensor Soil Hygrometer Humidity Detection Module for sale online | eBay? It claims to be corrosion resistant. Does anyone know what material are the probe tips made of? I can't seem to figure it out, it doesn't seem to be metallic. Is it really possible for this to be corrosion resistant?

The tips appear to be carbon rods. They are corrosion resistant. How ever, they can become polarized with various ions from soil components.

Paul

Paul_KD7HB:
The tips appear to be carbon rods. They are corrosion resistant. How ever, they can become polarized with various ions from soil components.

Paul

Thanks Paul. Does that mean it will be more prone to giving false readings? If so, is there anything I could do to counter or minimize its effects?

I have seen some Arduino forum threads relating to this and the suggestion was to alternate the voltage polarity going to the probes. Search the forums for soil moisture probe, or similar wording.

Paul