I went fishing for a thread about this. Can't seem to find one.
Just wanted to get all of your opinion on this. I've used Poland Spring gallon jugs for all 14 of mine. It seems to go over well.
What are some of you guys using?
Since water requirements vary for different styles of beer the best water is water of very low ion content which can be easily adjusted for the particular requirements of the brew day by adding a few salts.