Idk where you got getting another tent. I only said 1 tent. Also I seriously doubt 1 side of a plant would drastically outgrow the other side.
You said you wanted to seperate 1 tent for a sativa and possibly a couple indicas. Using 2 lights without a divider can accomplish the same thing. Plenty of people run multiple lights in 1 tent without any dividers. Its been suggested to me to buy multiple lights instead of 1 light for a 4x4 setup I have planned. Assuming people think the lights will be hung at the same height I believe, but contemplating this idea you can control light intensity with hang height rather than dimming controls. So essentially 1 light would be hung close and one light would be set at a higher power further away creating a balanced spread at the canopy heights. No extra tent no extra fans or filters no extra cost assuming at least 1 light has a dimmer. Im not sure if you have one light or 2. Im assuming 2 if you are planning on dividing your tent.
Its my opinion that a divider doesnt serve a purpose, and Im really trying to grasp what you're getting at and maybe something just isnt clicking for me.