I have read that distilled water should not be used-I use water that comes through a filter in my refrigerator. In the past, I had a filter that had been made to use with irons. You just filled the reservoir with tap water, let it go down through the filtering material, squeeze the sides of the plastic container and into the iron. It worked well and the material used for the filtering agent could be replaced. It disappeared somewhere in a move. I don't know if this type of gadget is available now.