Seems like it would work to me but I don't have all the parts and pieces laid out in front of me.
For the sensor. You could use an old white labs vial with a hole drilled in the top. Silicone it up and you have a water proof sensor.
That's my only contribution. Sorry it doesn't answer your question.
Tanglewood Brewing Co.
primary: Off the Wagon IPA,
secondary:5 Turns Vienna Lager
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