you should check out rosemans thread called the diy odor control bucket.. its looks pretty sweet.. he takes some of that ona and mixes it with water and gets a bucket and drills some holes around the bottom of the bucket, adds a few inches of the ona/ water mix, and places a fan on top of the bucket so that it sucks out the dirty smelly air from the room and forces it through the ona mix and it comes out the holes laundry fresh.. looks great and he says it works great for smaller grows.. check it out if you get a chance..