ok cool tube has open ends,,one end has the bulb fixture,,hook you vent hose to that end,when you unhook the fan,take filter off,after that turn fan on the side that is pushing air from it,hook that side to the filter,,the side that sucking air,that goes to vent hose on end of cool tube,,thats it,if you took that fan and filter out of tent right now and turned it on ,it would be sucking threw the filter,your just turning the fan around to do opisite if you dig,,it will push air out the filter instead of suck it in,,put the fan and filter on outside of tent on top of it,,dont weight that much,just a simple piece of plywood laying across top of tent will do just fine,,the heat and smell will still be filtered it will just come out instead of in,,the room temp will cool the room and heat coming out from the hid lighting and the smell wont be there either unless you need a new filter,,i have taken the charcoal out of them and with propane torch burned off all crap on it,just dont let it ash it will burn off and put it back in the filter,,im cheap though i get my money worth out of everything,lmao that charcoal has some kind of coating on it,and even though they claim its charcoal it is but coconut hulls,,but sweep the torch over it not igniting it and it cleans up