google : ona breeze. works for me. i used a filter now but still have this as a back up. quick edit... works really good..... as long as you keep the ona fresh... get lazy or the level gets low it will stink in a hurry so buy more then you need
Ok ill have to take a look at that dude....looking to start my second grow and this time it will be not as secure
You have to exhaust the stale air somehow and get fresh air in. You can't have a non-exhaust grow room.
You can grow in a completely sealed area, and run a fan filter combo inside the grow room to help with the smell inside the room. However, since you have no fan creating negative pressure any tiny little spot where it isnt sealed can and most likely will let stinky air out. Also, as Toasty said plants need air. If your grow gets absolutely no fresh air coming in, it would be wise to consider supplementing co2.