ventilation has consistently been the most frustrating aspect of indoor growing for me. Now I find myself in yet another situation where I need to move forward but cannot make up my mind on what exactly to do. If I ask questions that have been asked and answered time and time again I apologize, I've read and I've researched but feel like I need some input from those more experienced than me. I've got a 6x3x6 box I've got one 600 hps in one half and am planning on getting another for the other half. 6" hurricane pulling from the light and a 4" hurricane on the ceiling connected to a scrubber I've got 7 4" intake holes on the sides and front. this box is in decent sized bedroom. it does ok but temps creeping up to high 80s and its not even summer yet and I only have one light... I know the problem is my intake air is stale shitty warm indoor air made worse by the box exhausting into the room. there is a window I could exhaust air out and bring fresh air in but this is a second story room on a rental by a residential road, Id rather not have ducting sticking out my window. though if I have to I will. I am legal I jus would rather not flaunt it. I've got a 4" blower I was thinking of sticking on one of the intakes if I do put it to the window. I've also been reading about sealed rooms and ac. I do have a small window ac unit. eventually I would love to seal this box but right now the thought of more construction more money is overwhelming. but if that's my best option and I plan on it anyway Ill make it happen. what would I need to get for co2 and what would I be looking at spending? I'm jus lookin for any input any ideas sorry if this is unclear I tried to cover everything as quickly as I could.. thanks in advance