just put a bowl of water in ur grow room it wit put more moisture in the air but not 2 much ya dont wana over do itGood luck on this, I just suffered from the opposite of this issue. My humidity was dropping to like 20% with lights off.
got a humidifier and i sit about 50-55% at all times.
It was meant 4 the other guy how had very little moisture in the air an a fan wud b cheaper the a dehumidifer but its always handly if u have the cash lying aroundbowl in the room?wouldnt that bring humidity up? i need it to go down.no money issues here if my best bet it too buy a dehumidifer, i will.no mold or any signs of any.