Originally Posted by Ghost420

what about an ozone admiter how do those work for a grow of about 2-3 plants?

Originally Posted by Londoner

ok so you u have two equal sized rooms for veg and flower, to light both those rooms ideally you'd need 2x600w halides for veg and 2x600w hps for bloom, how come u only got 6' ceiling height with those sized rooms? I personally would keep the rooms intakes and exhausts independent of eachother, because the already heated air from yr veg room will cause you problems in yr flower room(drawing already warm air through yr cooltubes will greatly reduce their efficiency) that inline fan i use is 5" and pulls 240 cubic metres per hour, but my bloom tent is only 1.2x1.2x2m il let u do the math to convert that to cfm lol. id put yr 2 hps in cooltubes inline with maybe 3' of duct inbetween the two tubes then use the same configuration as me with fan and filter mounted to the top of yr room in the middle of the ceiling, blowing down to the cooltubes then out the room, and the same with the veg room using the halides, but id use a minimum of an 8" inline fan/filter/ducting for each room with duct reducers at cooltube sites, maybe even 10" because of the larger room sizes and two cooltubes per room. Ensure both rooms are sealed and airtight apart from yr passive intakes to ensure air is only being drawn thru the passives low down in the room and drawn over/thru the plants before it reaches the filter/fan. It is possible to extract/filter air from two rooms using one fan/filter but i wouldnt do it with the cooltubes, by using large passives in veg room then light baffled vents or ducts between the two rooms then use the biggest extract fan/filter/duct you can get on the outside of flower room sucking air thru both rooms and filtering by blowing thru the filter instead of sucking thru.