co2 would benefit your plants no matter how big or small the space. You just want to make sure not to over do it or you can kill your babies. My room is constantly being exhausted so in my case I would have to try pretty damn hard to raise the co2 ppm high enough to damage the plants. This is my first time using co2, so I'm still experimenting. From what I understand, normal air contains around 300ppm of co2, plants would ideally like between 700 - 1000 ppm, start to burn at 2000ppm and die at around 5000ppm, so your threshold for experimentation is pretty large before you do damage, as long as you're careful. I don't have any kind of meter to gauge how much co2 is in the air but like I was saying, I have fresh HEPA filtered air coming in to the room constantly at around 150cfm, so I'm not to worried about burning them. Best advice I could give would be to start out small and see how everything responds and work your way up from there. Give it some time too, I didn't start seeing major results for a few days after starting co2, but after the first batch ran out I noticed a definite difference in the amount of new foliage the plants had produced. with co2 they seem to stretch less and produce more foliage in between nodes. I've also noticed that with co2 side-branching is majorly emphasized. If you want instructions on how I made the generators I'll try to find the youtube video I found most helpful. There's a lot of **** advice out there and it seems like there were only a few helpful sites. I'll compile a list of useful info and post it here later today.