Lower RH or higher Co2

Constant replenishment of air provides as much co2 as is needed. Co2 is only useful once all 9 growth rules have been met and you plan to push past limits. Cellular respiration is what happens at night. Photosynthesis happens during day. The plant pumps co2 back Into the tent mostly at night as a byproduct. Rh again is another metric that needs updating on this site, Rh daytime can differ greatly from night, with the temp drops at night the air will hold less moisture, the plant Luke's to eject moisture also as a byproduct at night. So if you only measure 55 rh daytime it's possible this is rising to 70+ overnight. Moisture levels above 70rh% and above 77 farenheight are optimal breeding grounds for bacteria so make sure your air game is on point. When your plant's wake up in the Morning co2 levels will be high and she will slowly eat the co2 through the day.

Lower RH during flowering. Like 40 percent is ideal for heavy flowering. It helps keep bud from getting any RH related issues.