I only drink tap water because distilled is expensive / hard to come by / requires equipment. I am fasting mainly for weight loss, however one day I may use distilled.
The general agreement on this forum is distilled water best, but tap water acceptable.
Occasionally there may be conflicting posts, but if there are read the whole thread to see the argument on both sides
EDIT
I forgot to say, I have an inline water filter, so I drink filtered tap water