What's up Vex.... sorry about the shock and awe
. It's good to know I'm doing something right..
What's up Stav. I'm digging your grow journal and I kinda wanna be just like you..
I'll keep a eye out for those autos. I might be adding another t5 soon so I can have two trays but plans might change. I'm kinda running out of room for genetics and I have some big plans for the future so things might change a bit. Ive been really interested in breeding lately.
What's up Fertilizer.. The only reason I chose the veg tent I did was due to space constraints and the size of the equipment I had available. I already had a 4ft t5 so I needed a tent to fit the light. I wish I had a 6 bulb T5 Because the 4 bulb just doesn't fully cover the canopy in my 4x2. My veg tent is only 4ft tall and I regret not getting something taller but it forces me to keep my plants short which has helped tremendously in flower.
A 3x3 sound like a nice space to veg. The square floor space will fit 3 plants easily. You could probably even fits some clones in there too.
My exhaust system runs two 6 inch fans with speed controllers. Ones a hydro farm and the other is a vivosun from amazon. All the aluminum ducting im using is lined with black on the inside to help with light leaks. The fan in the veg tent uses a bug screen and the tents passive intakes. It sucks air in from the passive intakes and blows the air into my flower tent. The fan in my veg tent is about half speed.
The flowering tent has a 6inch fan and a carbon filter. This fan is at full blast and all passive intakes are closed in flowering. All the air coming into my flowering tent comes from the veg tents fan. I just adjust the veg tents fan speed so that the flowering tent still has a little negative pressure. If I turn the veg tents fan off my flowering tent sucks up like a Crack head.. lol. The passive system your describing may work but the slow draw from your veg tent means heat will build up and your flowering tent will be getting hot humid air drawn in. It's also a lot of work and stress for your one fan that can lead to a fan failure. You could use a small duct fan but I don't think it will be strong enough... plus summers coming, a second fan is a must.