yes, it just all depends.theres a lot of factors but count on a smell.build the filter and have it ready 2 go just in case.if your box is say in a back bedroom or some thing similar i wouldnt worry about it. the smell wont flood the neighbor hood or anything.its nothing like coming coming home 2 see 2 cop cars in your drive way with some one pulled over and leaning on the garage door 2 ft from your 12 plants on there last week of flower:wtf: lets just say i almost pissed my self.bought a ozone generator that day.