The simplest way is with a co2 generator and a cyclestat timer. The best way is a PPM shut off, but that's at least $450.
Opie Yutts Reviewed by Opie Yutts on . CO2 so what the simplest and cheapest way to provide co2 for a growroom?i expect the air around here is 500 to 600 ppm since i am right on a busy main road near a town centre in a city...last time i tested a different grow room in flower i still got a decent 400 ppm and all that was exhausting i ntheir was a decent sized air pump getting rid of air into the attic and it was only a small room packed full of blueberry.... what about this sugar/yeast/water idea? what about burning candles in the Rating: 5