I think it is a good idea to keep it as high as possible. my reason for this is my grow room is in the basement and before I odor controled you could smell it up straits but not so much on the basement floor. this leaves me to believe the odor raises, second you will be creating more air movement in the hottest part of your grow room. with more air movement in the hottest area it will make for good air exchage and allow you a cooler grow room! I have mine hanging in the highest spot I could get it