pH sensor returning negative value in tandem with soil moisture sensor

Using Arduino Sensors
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For a school project, my partner and I are working on creating a smart sensor station. It utilizes the following.

  • Uno R3 Board
  • Sensors
    • SEN-13637 Soil Moisture Sensor
    • HUMI-01
    • 161 Photoresistor
    • Analog pH Sensor/Meter V2
  • Qunqi 400 Tie Point Mini Breadboard
  • Dahszhi 170 Tie Point Mini Breadboard
  • IIC/I2C LCD2004 4x20 LCD

Our issue thus far is that when the soil moisture sensor and the analog pH sensor/meter V2 are used in tandem, the pH sensor outputs a negative value. More specifically, when they're both in the same patch of soil this occurs. We've tried testing it numerous times, and found that if they're used separately in different containers of soil, it outputs the data just fine. We've looked through the datasheets and scoured online for someone with a similar problem, but were unable to find a solution. We believe it has something to do with the way they input data. The soil moisture sensor specifically measures it's output by the conductivity of what touches it prongs, which is what makes us think that.

If need be, we can upload pictures or our code.

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Please, do post your code in code tags,

Please do upload pictures of your project.

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Both sensors can't be used in the same medium, due to galvanic coupling (short circuit).
You can try replacing the (useless) SEN-13637 with a capacitive moisture sensor.
Capacitive sensors don't have a conductive path to the soil, but I don't know if the layer of insulation on the sensor is enough to not fully disturb the Ph sensor.
Leo..

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