Quote Originally Posted by Mr. Clandestine
I had the liberty of borrowing a C02 system during my last grow. Complete with tank, emitters, timers, and all that jazz. I didn't have a clue what I was doing, and only used it while I was vegging. But the plants showed definitive increases in growth in the short time that I used it before having to return it. My room wasn't completely sealed, and so probably made it less useful than it should have been... but I'll definitely be using it again. When I can scrounge up the money to buy the equipment for myself...
Ohh what a tease!

Co2 definitely helps. plants use co2 as ONE of the main blocks of photosynthesis, You must have enough light, water, nutrients, and a (mostly)sealed area for Co2 to work correctly. based on a lot a research ive seen 1400-1700ppm is optimum for most strains w/ some able to handle up to 2000ppm w/ enough light. IMO from what ive read.