I bought a 50# bag of sea salt for my soaker tub. I had placed it in the closet while painting the bathroom. The salt absorbed the moisture in the air and dropped my room to 40% from 60%. It was unintentional, a happy accident. It made sense the more I thought of it, salt draws moisture from products like meat and fish. So why not from the air?
I paid probably 60 cents a pound.