This is SO cool!!! I've been wanting to try this for SO long!!! Glad to see I'm not the only one thinking cubically. I've read through all 19 pages and the only concern I have is the shrinking canopy as it grows towards the light. After a good bleezy and a long hard look at my canopy (21sqft, 5 girls 5 gal each, under 3x 400hps, trained), my canopy is 8"-12" thick, but EVERYTHING is growing towards those 3 lights. Yes, in a vertical tube, there will be some crowding, but I think if you keep everything even, all will be well. Think....a 4' tall doughnut about a foot thick of dense nugs.
I'm doing the same idea but with 31" dia x 3' tall around a single 400, 4x 5 gal, 3 sets each room, two rooms, perpetual. In my space, room is not a luxury, so I'm making the base of mine spin....lazy Susan style. Now I only need access to one plant at a time....just a thought....might make it to where you could get one more of these in YOUR space?
-Bender