Hello all. This is my first post and my first Arduino adventure, so please bear with me should I say something incredibly wrong or stupid.
I bought an Arduino Uno in order to build a simple fishtank monitor by reading a DS18B20 thermometer and a SEN0161-V2 pH probe and showing the values on an LCD. Attached you can find the schematics of the project.
The circuit should be now final, but I'm having a weird behaviour with the pH probe: while outside of the tank, and with very small amounts of water, the readings are consistent, when I put the probe in the tank for the final deployment I get different values every read (+/- 0.5 pH), basically bouncing between each others. As I said, when I was calibrating the probe and writing the code the values were a lot more consistent, with an average floating of about 0.03 pH, which I guess is a decent error for a low end probe.
What can I do to troubleshoot my issue? There's clearly something I am missing, but again being pretty much a newbie with Arduino and electronics in general, I really don't know what to do right now.
Thanks everyone!
