Maybe a stupid question, but..

[Evelon]

Even though I'm only on my 2nd grow I have read growbooks and growguides and most of them explain the chemical process when adding CO2, and that it enhances the speed of growth "up to double" while flowering, etc. But there's no mentioning about CO2 during vegging. Am I missing something (like a screw in my head)?

Why not use CO2 during vegging aswell?

 

[GanjaGuru]

CO2 enhances growth during veg and the first 3 weeks of flowering. After that it does little.
CO2 may increase growth "up to double" over a similar grow with little or no ventilation. But that means growth rate. In other words, 2 plants 1 w/CO2, 1 w/none. Say you're gonna raise them to 18" before switching to 12/12. The plant with extra CO2 will get to 18" before the one without.

But CO2 augmentation is expensive. The only effective way to use it involves a sealed growspace, regulator, emitter, extra fans/timers and a way to measure levels (reusable meters are $500.00).
But for like 30 bux you can instead put in flo-thru ventilation which is way most cost effective than CO2 augmentation.
CO2 aumentation does not bing bigger buds per se. It means the same size buds but quicker since it shaves time off of veg.

Imo, CO2 augmentation if for the commercial grower.

 

[Evelon]

Thanks GanjaGuru for straightening things out, and adding useful info!

 

[Biffdoggie]

Ganja is right about that one, there is a formula of moving air that will get you almost as close to using Co2 as actually using it. I will try to find it.