according to henk van dalen tee...........for normal development and to be able to change air quality regularly enough without dropping temps, you nedd a min of 1 meter square per plant if medium sized like a fem reg. 1 max 2 plants in a 1.5m square tent is max. other wise "yield" will be comparative to 4 in same space. Ergonomic impact of proximity. The plants know they are close up etc.......respiration product spewing onto each other is blamed. Ive tried 8 and 6 and 4 and even 15 in a 1.5 yield only varied by 25% top and toe.
So would take a 4m by 3m room with a 40% negative air pressure induction over a tent any day. if you want to run an auto or a mother while doing fem regs get a tent !! the air volume in a small room is triple or more. so 8 ina room 4 by 3m is where you are aiming..........for ease of environmental control and lower bud rot risk due to better air volume and circulation.........you only need to change room air volume every hour and not every 10 mins due to small space in a small tent etc, air con free standing units can be used to much greater effect in 10 cubic meters, u may need one to keep temps down, down there !! a tent will condensate on the outside, a room will breath homogenous slow thermal exchange etc.......and wont condensate on the outside !!............room win over tent ??.....air con is 1.5kw hr though !!.........and air is 38c ?? 12 above required ??...............rh at 38c 85% ??............its a full dehumidify air con set required as in USA !!........AB......