High GC! I'm still designing my first growroom and I must now build an air filter for odour control. I looked at many DIY designs on the web but I was not satisfied and came up with my own. I am at work now and the only soft I could use to draw anything is MS Paint, so my drawing is cheap but you will get the point. It's a 2.5 gallon bucket, with a couple 2" diameter holes in the bottom. I lay a layer of foam filter cut to shape to cover the bottom of the bucket (and the holes). I lay a layer of activated carbon pellets over the foam, then another layer of foam (probably optionnal). Cut a 6" hole in the bucket's lid, and fit a 90 elbow and connect to 490 CFM in-line blower, then 1' of duct and it exits the room. I'm not sure if it makes sense explaned that way, I'd like to know what you think of it. Here is my drawing, anyway I'd like some comments and ideas. Thanks!