Could the commercially-available sensors listed on this page: https://publiclab.org/wiki/water-se...
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That's true Chris @cfastie! You read through to the heart of my internal question on this too: is it worth it to try to hack commercially available sensors to do something beyond / different from what they were produced to do, and I appreciate your candor in spelling out that the answer is probably no. Thank you for that. Cheers!