I'm sorry if I came off wrong there Ninja....I was quite serious when I said if it's a small grow, just go breathe on it. You are a co2 generator and if your grow is small, say a closet, small tent, or cabinet...you can probably increase your yield slightly, or at the least make your plants a little bit healthier just by going and singing or breathing on them for 10-15 mins several times a day(singing supposedly is when you max at making co2)...this does several things for you and your plants...you get some real o2, the plants get some added co2, you get to spend some quality time with them and if you're observant and learn to "read" your plants, (something all noobs and amateurs alike should aspire to) they will "tell" you what's going on with them and you'll notice things about them you did not before.

The other thing is safety and like Lynhal said, co2 used improperly can kill your plants and you and your pets. OM is correct in saying there are other ways to make co2 cheaper than dry ice, or spending a couple c-notes on a tank and regulator, but I have to tell you they can be messy and quite stinky if you live where you grow. OPG (other peoples grow) yea, stink it up with co2 production! (I like how OM said he did that at somebody else's grow....LOL! These plants can prolly take more of it than we can! Big greenhouses should prolly have a sophisticated co2 dispensing and monitoring system, but most "me and my bros" grows don't need to add it....add some light and a few more plants if you need a bigger yield.
TANKJR Reviewed by TANKJR on . why co2???? I keep hearing about people adding co2 to their grow room and or tent. What is this for and is it needed? Rating: 5