Quote Originally Posted by ozzyleven
I agree with LuciferN, but if you were to do the dry ice thing I would not put it directly on the soil, maybe in a container centered between the plants? Really though, if you do the math, you would be better off to save up for a CO2 tank and regulator, after one harvest the tank and regulator will be cheaper than supplying 5+ pounds of CO2 everyday to give an adequate amount.
This is quite true ozzyleven, on the long run the tank and the regulator is better, you can switch it off when the lights are out or even put it on the same timer as the lights! Plus it will last longer compare to dry ice and it easier to manage the amount of Co2 release by it.