RE:RE:RE:RE:HempMy opinion only FibTrader as I'm not qualified other than to say I'm familiar with the growing stages of MJ.
There are rooms specifically devoted for rooting and young plants that are under different lighting and duration of lighting than they are when they begin to flower to harvest. Its the pre-flower stage that provides Co2 with the greatest growing benefit to MJ plants with no adverse affects.
Hope that helps and anyone with more info please jump in.