Grabbed the DS18B20's for temperature readings (looks like a transistor, i'm going to mount them into an aluminum probe scenario - then encase in epoxy for reef-safety...
Also grabbed a pair of photoelectric resistors - basically to confirm the lights are in fact on... how i'm going to tie those in... Not so sure
Looks like I might need a 3rd shield with just an i2c port expander on it - as I'm going to run out of analog inputs quick at this rate...
Highly recomend HVW, these guys are great to deal with - extremely helpful thus far.
Hopefully I'll have the temp & pH circuits sorted this weekend.
Overall plan, is to connect the arduino to a wifi router running dd-wrt (fonera 2100 in my case) use it for the logging & give myself a web based front end similar to the wrrc project from reef central. Not a big fan of the LCD's at the tank - easier to just log into a nice webpage and see the graphs as to how/what things are happening than to try to pull that same info from a little lcd...