Looking for some help to design/build an automatic PH controller - cheap

[anon32470837]

@Northern_Loki

If you are doing PH, you’ll want to measure temperature as well for compensation. So, either two probes (temperature and PH) or a probe with a temperature output, too.

And, what @lefthandseeds has said. A PH probe with a constant service/immersion rating if the probe is going to remain in solution for long periods.
See Leaving the pH probe in RDWC reservoir...?

Dang. I assumed all the probes had temp sensors built in. Looks like its only the $$$ ones. So, that adds at least another $40 to the cost for a temp prob and board, plus more programming.

Well, crap. This is becomming more and more unlikely.