Thinking of fasting-need info. please

I have been reading about fasting and think I would like to try it regularly. I already drink lots of water, but as I've been researching fasting, I have a question.

What kind of water should I drink? I drink well water. It is really good. I can't see any contaminants in it. That doesn't mean that there aren't any, but I don't see them. Some experts reccommend distilled water. Some say no because distilled water is "dead". There is also reverse osmosis, ionic, spring water, etc. I don't know what to choose. I don't want to continue to drink well water if it's putting things into my body that I'm trying to get rid of. I've also read that filtering it is bad, too, because of the toxins the filter releases.

I am confused. What do you reccommend?
Thanks,
Tisha