Those are images of part of the air flow configuration for the re built grow area. There is a (TD-160) 4" or 6" inline extractor that sucked in; and there was a (TD-500?) 8" one that sucked out. They never came on at the same time and were controlled with a digital thermostat from Maplin. There was a 6" or 8" normal fan suspended from the ceiling space to move the air around. The air flow was sweet and the total volume of the area was around 3-4 cubic meter i think!. The Area was sealed and had cut outs for ducting. No smell filters we included in the design. Altho I've took all my equipment out the construction It still stands and is very very sturdy. That was all in someone's loft space... Pics are a bit poop actually..!