depends on waht strain you are growing some can smell a shit load like Skunk an some dont like my NlxBigBud very mild smell...if your looking to get rid of smells theres lots of ways you can do it...car freshener etc anything like that jus not on the plants! but the best way is to get a extractor fan with some piping of some sort & a carbon filter...fit the fan in the grow room connected to the piping prefably leading out of the grow room with a carbon filter on the end of it..should see you fine for 12 months or so...if your looking on where to find all this equipment jus do a goole search for hydroponics an go threw there stock list shouldnt be hard to find what you need!...
Gd luck!