What can I do to mask up the odor of cannabis in my growing room??

Hi there.. to mask the smell you will need to get a carbon filter that's properly sized for the size of your tent/growroom.. the carbon filter will have to be connected to a fan, and the fan will pull the air through the filter to the outside. If the fan/filter combination is properly sized then this will pretty much eliminate all smells. Just be sure that you don't get a filter that's too small (and can't handle the amount of required air that needs to be cleaned), or a fan that's too big (if the air is being pulled too quickly through the fan, the carbon charcoal inside the filter will not be able to remove the odor from the air). If you have the right combination of both, then you'll be fine inside the house.. inside the tent it will still smell of course, but as long as everything's properly sized you will be fine. happy growing!