I just read this page ...
https://www.rollitup.org/t/max-ppf-ppfd-with-and-without-co2.921830/
i wont be concerned about that with the 3x3 area however it is in the area where I have other COB bars, and I am running Co2.
I just watched @Growmau5 video and looks like i may be covered.
Why do you...