I am amazed by the number of people who have such faith in "any" kind of water tank. <img src="http://www.traveltalkonline.com/forums/images/graemlins/Yikes.gif" alt="" />

In the 70's, I was the manager of a very, very large swimming pool in the Toronto area. When the pool was first built, we had to drain the town's water tank to fill it. The water in the pool was the most gorgeous emerald green I ever saw!

It was so contaminated that live frogs were actually living in it. We had to pump it all out, clean the pool walls and bottom with muriatic acid to try to get the bright green stains out. That didn't work so we had to have to whole thing resurfaced and start over. That was the town's drinking water. I have never touched tap water since!

Part of my pool management training required that I take a college course in potable water. I have tested water in various boat tanks over the years, including my own boat, and there is no way in this world I would ever drink it untreated, even after boiling it.

That being said, my sister died in 1979, at the age of 28 after drinking bottled water in Mexico. They were staying at the Puerta Viarta Holiday Inn and after she died, we discovered that the bottled water they sold at the hotel was actually bottled directly from the hotel cistern.

Personally, I would buy brand name bottled water or a brand that people can vouch for.