Wanted to add to this thread since it comes up in a Google search.
I built a new sealed building and the flower room is completely sealed.it will hold co2 ppm for hrs without going down.
Anyway I ran my clones like I always and noticed immediately some fucked up issues.
Leaves drooping real bad dark purple stems,leaf colors were yellowish not green.
I have never had this problem.im in dwc and on bottled co2.
Well I tried to nail down every possible cause and could not figure out wtf was going on.started to think I forgot how to grow like wtf am.i slipping?
So after a bunch of research and thinking I'm having some kind of off gas issue.my plants really looked like the roots were oxygen deprived but im running the same exact amount of air I always run.
So I decided to add dampers and intake and exhaust to exchange the air every 3 hrs for 6 minutes.
Within 12 hrs plants were 100 percent better.after a day they have exploded.
Anyone who thinks you donr need to exchange air in a sealed room already has small air leaks they just dont know it.im convinced this was an issue
After a day of air exchanges they are perked up and looking 100 times better.
They looked so fucked up 3 days ago I was ashamed to take a pic