co2 bags vs DIY co2 generator

what is the cheapest way to get massive ammount of co2 for your plants?
whats the best way to use co2... i have a 4x4 600w tent 530cfm inline fan sucking air out...

....a 4x4 with a exhaust like that? and you want how much co2? Imho, no 'cheap' way to do that......but co2 does drop and heat rises so with your exhaust up high....geez. I just don't see it being worth it if you cant run sealed, or close to it, with ac and all...... Someone else have ideas? peace and good luck, gman

i gave a speed controller i can turn off the fan as well... i also have another manual spinning fan aimed at the bulb i can touch the light no problem my plants are basicly touching it too. And YEAH i want massive ammount of cheap co2 i know it is possible to feed my plants cheap co2 and benefit from it i just dont know how!!!!!!!

.......wishing I had an answer for you!! Someone will, I am sure....maybe in the diy threads??--->I seem to remember people doing co2 with some yeast bucket things, or something like that. I use the 20#bottles myself, completely sealed, and keep it between 1300-1500ppm with the cost at about $15 a week??, something like that. Small room too, being only 6x11, but completely sealed except for the one or two times I go in there at night(day 4 them). I know nothing about the 'bags' and have seen the little bucket boost deals(which don't seem cheap, all things considered)....and then comes into play the ppm's your running it/them at...how do yah know? Yeah, math I guess....but if your gonna diy it, I guess that's okay. Hey, great luck to you! I hope you get it/something figured out to your liking!! peace, gman