wow this is just what i was looking for i was looking at this C02 sensor you think it would work http://www.futurlec.com/CO2_Sensor.shtml .
plus i found this guy doing the almost the same thing he is trying to get funding to make a broad and a system to track everyone data to share it...
it is open source so it up to him and everyone that helps out how well it would work. the prototype look like its working. i asked if there could be a C02 sensor. it is open source so I was just think of doing a lot of the work my self making the sensor... it sound like he want to make...
Growerbot looks cool if it is open source that would make a good set up. Needs a C02 sensor what do you guys think. i love diy
http://www.kickstarter.com/projects/liseman/growerbot-your-social-gardening-assistant