I've been using dry ice in a styrofoam cooler with a couple holes poked in it, I work in a medical lab so it's free and accessible to me daily but I'm pretty sure you can buy it by the pound for dirt cheap.
ml2242 Reviewed by ml2242 on . CO2 solutions for micro grows I'm growing in about a 1.4x1.4 foot area where the plant pretty much takes up the entire area. I've heard how much CO2 can help a grow throughout all stages of development and thought it might be worth it to add some CO2 capabilities to my next grow. Do any of you have ideas about CO2 sources that are available short of just buying a cannister? Thanks. Rating: 5