When using distilled water, use caution. I don't mean that in a way that it will harm you, but I'm not sure how it reacts when using it in this situation. Distilled water is very aggressive. When you remove everything out of it (minerals and whatnot), it becomes very reactive and wants to neutrilize itself...at some point wants to balance it self out. It pulls ions from other sources to balance itself out. What it pulls out from where, I don't know. It also can have a very metallicy taste to it as well. I would recommend RO (Reverse Osmosis) water. If you have really bad water, you can save yourself in the long and purchase a small RO unit. I have no affiliation to this company, but you will not find a better price for the quality. www.purewaterclub.com
Just get the portable system PO-4-3P100. You can take it with you if need be and it has a set or replacement filters. Probably more info than you wanted.