This diagram shows the Green Air Regulator (BCDE-1) emitter system plugged into a CO2 monitor controller for the ultimate control of CO2 enrichment. The CO2 monitor controller will automatically maintain the proper CO2 levels continuously and coordinate CO2 enrichment with your exhaust functions. This system is plugged into the CT-DH-3 atmospheric controller and will defeat CO2 during darkness periods and while exhaust fans are on.