I use the funnel that came with the iron and distilled water. I have a Shark and the instructions said to use tap water, and my water is very soft, and filtered. I still feel better using distilled. The thing about my Shark is that it will quit steaming if it is only half full. I exchanged it and the new one does the same thing. For people who steam a lot I like the idea of using a garden jug and sprayer.