Electrolyte water?

OK, I am sue we are going to have a mix of opinions on this. I know some people advocate distilled water, personally I drink tap water, but my opinion - a gut feeling if you like - is that water from streams and rivers is the best, minus the pollution. This seems to be backed up in the FAQ at the top of the page, 3 years ago user #56153 wrote in "Water Fasting" at
//www.curezone.org/faq/q.asp?a=25,1787,2836&q=43
"clean mountain spring water is far more preferable then anything else!"

Now I know that some here prefer distilled water, but there are no straight lines in nature, and nothing is pure. I figure our ancestors would have fasted out of choice and necessity, and I wold tend to think they drank spring water rather than rain water, as it would have been readily available and did not require the use of containers. Therefore I think this is what our bodies have adapted to, and this MAY be a better choice for fasting.

On some of my longer fasts I have felt that there is something lacking before I reach the hunger stage, and I wonder if this is the minerals that would be present in spring water.

I also notice that the new "Facing the Fat" documentary
http://www.facingthefat.com
seems to promote the use of "smart water". The man who water fasted for 55 days in the movie actually drank Glaceau branded smart water that contained electrolytes.
http://www.lasplash.com/publish/cat_index_Beauty_and_Body/Glaceau_Smartwater-...
What do people think of this? Can it help extend a fast or ease the unpleasant symptoms?

Smart water is not on sale in the UK, so I was wondering if I could make my own! After a Google search I came up with something that cyclists use, they are tablets that you add to water. See
http://www.wiggle.co.uk/p/Cycle/7/Elete_Electrolyte_Tablets/5360036050/.
If I do a long fast this time and experience unpleasant symptoms, I was thinking of trying these rather than breaking the fast to see if it helps. I certainly don't think it would do any harm.

I am just curious to experiment. Opinions would be welcome!