Hello, I'm trying to build a hydrophonic irrigation computer system. One of the properties I need to measure is PH and/or TDS (Todal Disolved Solids). For the TDS I already found I can use a voltage divider and extrapolate the data I need. PH however is proving much more tricky. Aside from using pre-built sensors such as:
which are costly, can anyone help out with the code or other sensors I could use?