I have done lot's of searches on the site and can;t find anything to answer My question. Which is do you run low c02 durning veg? My girls were growing great in My room which is totally sealed my c02 readings were down to 170ppm so I fired up the c02 to try and kepp it around 300 400ppm reg air is 500ppm. Now they seem to have stopped growing taller was wondering if anyone new if c02 would cause them to stop. Like I said the room is sealed tight I run a/c and a DIY Under current 6 site system and to 1000w vert's with Growtronix DDC Controls.