advanced control

im newbie in growing..but an oldtime smoker..
my day job is a control engineer so i decided to mix business with pleasure..
i used a plc and hmi on a hydro system i built..some main features:
-temp control
-ph and ppm monitoring
-lights,pumps and vent control
-mini journal

the pics are a bit low res..on the touch screen it looks better..
any suggestion/thought will be appreciated..

more features:
ph and ppm calibration-2 points for ph(ph4 and ph7)..1 point for ppm
work with ec and ppm
temperature calibration
alarms-temperature out of range..ph and ppm out of range
lights working hours accumulator
recomended ppm for a specific week

in the future:
energy monitoring
alarms sent to my mobile phone

i used a ec/ph transmitter for a 0-5v signal to the plc..and cheap thermocouples for the temp
my plc is omrom cj and my touch screen hmi is omron nb
all the hardware was "borrowed" from work
all the software of the plc and hmi was written by me
my goal is to make this control system under 500$

How about humidity in room and soil. Need to think about the new ballasts that can be turned on and lumns adjusted with a computer. Start at 600 and ratchet up to 1000. Then super lumns to 1150 for the middle 2 to 4 hours then ratcet back down.

i didnt approched humidity yet..but all i need is some kind of humidity transmitter..for analog input.
same about the lights..a lumens sensor for feedback..and some kind of analog control of the ballasts.
but all this means more money..im just playing around for now..