Well, I looked at your ebay carbon filter and can pretty much give the advice of I dont think its enough. Im running an elf carbon filter in a 4x4 tent. I think its 5lbs of charcoal. Problem is MY WHOLE FUCKING ROOM REEKS OF WEED. I cant open my bedroom door except for short run through bursts. When I do open it, literally if its open for 5 minutes, the whole apartment reeks. 10 minutes and its out in the hall. So im investing in something 10-20lbs and I think ill still have issues so Im also looking into ozone and crap like that, Smell is way worse than I imagined and yes im growing skunk, but at 2 weeks flower if its bad, i think anything in late flower is going to be stank.
so step that up to 10lbs id say, and that little fan on that ebay thing you have aint going to do much either. Your definitely going to need more than that I hope you know. I have a 465cfm exhause on my tent, thats all I needed as the thing is so strong it sucks in the walls of the tent and no intake is needed. Only thing is not enough carbon, or fan is so strong its not giving the proper time for air to be filtered (too fast) to make a difference.
So not an expert but you need more id say.