thanks for the in put. still smells in attic where vent is, not grow room! built a carbon scrubber that should do it. 6" in line fan pushing thru scrubber......or should i pull air ... may not have enuff room to put scrubber in. closet is 31"x35"x8' running a 600w hps digital in that space. temps steady 75F to 78F lights on humidity 40- 50 %, lights off 68F. thanks to all for info ......grow well