This will be of great service. I can look over his stuff.
I forgot to mention some things that I planned on doing. Such as using a sensor to measure CO2, voltage (for shutting some systems down in case of low charge.) And PH anyways. I decided to update with my buy list.
I have been reading Raspberry Pi Home Automation with Arduino by Andrew K. Denis on my Kindle. (Which has some moments of insight, but a lot of concepts are familiar and leave me bored, but I have never worked with micro controllers so I am doing home work.) I guess to get some more beefy reads I am going to have to read some books on python, and c++ sub code.
So here is my buy list (and yes I am being cheap, if I break it, it's an easy replacement. and haven't gotten my relays yet)
PH
http://www.ebay.com/itm/201080663258?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Analog to Digital
http://www.ebay.com/itm/190888152989?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
GPIO expansion (in case I need it)
http://www.ebay.com/itm/400694139624?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Voltage sensor for monitoring my solar batteries
http://www.ebay.com/itm/380773553422?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Real Time Clock ( I figure I don't need it due to the Pi's internal clock, but if I do it's here if not I got a tool for a future project)
http://www.ebay.com/itm/301141108103?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
CO2 and hazardous gas sensor to monitor rocket mass stove output and "plant oxygen"
http://www.ebay.com/itm/271340980895?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
A day light sensor to measure amount of sunlight and also help regulate the heating an cooling system ie; fan off in summer heat, or heater on at dusk, basically a buffer between my temperature sensor thermostat http://www.ebay.com/itm/310828123345?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
A Barometer just cause I am already monitoring other enviromental factors and if pressure drops suddenly we most likely gonna get rain. http://www.ebay.com/itm/371043374165?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
Temp and humidity sensors for compare and contrast of temps and moisture. Also thermostat controls.
http://www.ebay.com/itm/111238295400?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
water level sensors for activating a reserve (rain water tank) to add water if fish tank level drops to low.
http://www.ebay.com/itm/360902277336?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
A mega cause I figure I am going to have this baby loaded down with I/O ( you guys tell me if I need more than this mega, Arduino is open source so this isn't pirated board, right?)
http://www.ebay.com/itm/251427905210?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
and I am building this with a buffer chip just cause I think it may help with expansion in the future, and it's a little more modest (so I'll tackle it while I am reading about PI and Arduino code.)
http://www.instructables.com/id/The-Raspberry-Pi-Arduino-Connection/step1/Parts-needed/
I haven't bought relays boards because, I haven't decided on what voltage I want some of the new hardware to be.
Oh and I will be working on a "sketch" soon, I hope.
@wildbill I plan on having the Pi hooked to my WiFi network. The Arduino and sensors are close enough to where my Pi will broadcast. That I probably won't have a cable running longer than 5foot (1.5meters)
The green house is 8x12feet, with a 300+gallon (1100+litre) tank, but all my sensors can be confined to a very small portion of this area, and Network to the outside world via WiFi.