I've been experimenting. I added water everyday to my humidifier, just a few drops to moisten it up, and I watched the humidity raise a percent a day. It hit 75% for the first time ever for me a few days ago:) I havent added water since and it has kept it's humidity!! I am so proud:) I think I may add a few drops to it tonight just to maintain it at 75%. I was gonna wait till it dropped to 74%(I assumed tomorrow maybe) before adding more until I read monkeys advice. My humidor has more cigars in it now then it ever has and I think that helps it keep its humidity as well. It's not ALL Just open space anymore. I still have plenty of room though!