the hardware aspect is hellishly confusing to me, because I've never gotten this far into components. I can put together a PC no problem...
is the relay board an electrical relay?
The relay board is just an electrical switch that controls a mains line. When a 5V signal is sent to it, it will open. You can get the standard mechanical relays, or the more expensive solid state ones.
That RTC chip looks pretty cool, DarkBlade, thanks for pointing that out!
Is that pH probe the same as e Bay item 170752579436? I've been thinking about snagging it but dont know if it's any good. Are pH probes a "you get what you pay for" kinda thing? Also, what board are you connecting the probe to?
I personally like the DS3231 chip, since the DS1307 does seem to drift. The libraries are interchangeable, so there is no extra work involved.
I just got my pH probe locally; cost me $15. The one I am using seems to work fine. I am connecting the probe to a pH meter breakout board; there are lots out there. I got this one from a friend who had a spare. You can build your own for ~$10-15, and save some money, though (I was going to go this route).