now then bricktop, thanks 4 ya reply just wot i was looking 4. I am growing in an 8x8 room with about 35 babies, no ventilation only wot i provide which is a 6inc intake ov fresh air which i think is fine but i am worried with my exhust system will bring me a bit 2 much attention, my room is situated in a built up area where their is not much privacy. any suggestions fella.