Air Quality & Odour Control
Cannabis plants require fresh air, especially during vegetative growth and flowering stages. A good ventilation system can prevent mold, replenish fresh air into the grow room, stabilize humidity and control airflow. Your ventilation system should include a passive intake to bring air in and an active vent to take air out. Grow tents almost always have holes to allow for easy venting.
Cannabis is also notorious for its odour and for your grow's security, it is best to deal with these odours before they leave the grow room.