We are on our way to Siem Reap in a couple of weeks so I would like to thank you all for this information.

It would be good to have this thread stay at the top to forewarn other travellers.

The one in Thailand (available on the islands especially for about a third of the cost of other water) came in slightly whiter bottles, but the look exactly like this. We were told that this water is only filtered. As soon as we stopped drinking it, the problems went away.

We just returned from 2 weeks in Vietnam and 2 days in Siem Reap. We took and used a water purifier on our entire trip. Made our own bottled water daily. Used our own water to make coffee each morning and never ate outside of the well known tourist hotels. We only drank fresh pineapple juice at the hotels when it was available.(yes, I know they use water to mix it - the only time we gambled - that pineapple juice is so good!!) We never drank coffee or tea or ate noodle soups. Drank only bottled beer that we opened ourselves at the table. It wasn't until Siem Reap did we drink bottled water offered to us by our guide pon heary's brother, Dara. The same day we got sick. Explosive, gut-wrenching waves of pain and diarrhea. Terrible! With that being said. I cannot say with certainty that it was that bottled water that made us sick. Perhaps a flu bug. Maybe just a change in diet. Different oils used in cooking, different spices, etc. *shrug* I don't know, but it sure put us down for several days.
What I am certain of is, on the overnight train to Sapa there was several bottles of sealed water on the table for us have. I opened one to use with a cloth to wash my face and hands. When I peeled the outer seal off I noticed that it was wet. The cap was not tight AND it was dirty under the cap. I disposed of it and got another bottle. Same thing. It had been opened and a make-shift seal was put over the lid. Another trick we saw in Vietnam was bottle water that said, "USA" claiming to be purified by NASA space technology. This is not bottled water from USA. It is a Vietnam bottled water with a name to fool you. Clever marketing trick.

Was the bottled water you drank in Siem Reap like that shown in the photo link?

book_it, it was interesting to hear your story about water in VN, especially the "NASA-purified" water. VN has very different ideas about intellectual property than we do. You may have been approached to buy books by sellers around the lake in Hanoi - all of the books are copies of the published books. In the duty free shops in the airport, you'll come across Cognac and Scotch at really low prices, and you'll be tempted until you read the labels carefully. My favorite was the one that said "Made in Scotchland."

A number of the bottles we opened in vietnam were sealed with plastic, and wet. At first i was worried, then i drank them anyway. No problems :)

I just recently toured with Dara and had no problems whatsoever with the sealed bottled water he gave me to drink.

This is such a great site! Thanks to everyone for the warning!

I got food/water poisoning in India once and thought I was going to die! It's the most dreadful type of illness because it comes on so suddenly and takes over completely. My sympathies to all those who got ill on SE bottled water!

Is there anything else safe to drink besides Coke? (Now i'm going to be cautious about drinking even bottled fruit juices!)

book_it, can you share what kind of water purifier you used?

easytraveler, this is posted here because the experience of getting bottled water that is not ok is very rare. I've purchased and consumed bottled water all over SE Asia without any problems. I do make sure thay are sealed. Of course, hot beverages such as coffee and tea are safe.

My thanks also - will be in Siem Reap in early Feb and fore-warned is fore-armed.

So the question now might be - is there a brand of bottled water sold in Siem Reap that is absolutely safe for certain ? Are imported brands like Dasani or Aqafina available there ?

Kathie, thanks for the clarification. :)

Yes, I too have had bottled water all over Asia and usually use it to brush teeth, etc. as well as to drink, so it's a bit of a shocker to have a warning about any bottled water anywhere.

How does one tell a good bottle from a bad bottle? Water is not something that one can do without.

Would you recommend that I take a water purifier on my next trip? (Planning Thailand and Vietnam, maybe South China). Thanks for any help you can offer.

All the water we drank in all 4 countries was completely fine besides the water featured in the link above, which is just filtered water. If you buy the normal-looking clear bottles of any brand, you'll be fine.

I believe the water filter we took this time was an MSR mini with a ceramic filter. Works wonderful in bathroom sinks. Fast, easy. The bottle fits nicely in our backpack to carry. Much cheaper than buying bottle water all the time.
Anyway, I need to assure people that most liquids are safe to drink, including soups, tea and coffee. But, because we are older travelers and have touchy systems that unbalance easy, we use more caution than perhaps others need to. Dara in Siem Reap is a wonderful man and great guide I would never suggest he gave out BAD bottle water. Perhaps it was just a change in the mineral content from our water to his bottled water or like I said, a flu bug or even slight food poisoning (which can happen in any restaurant, including 5 star hotels) I suggest all travelers use a little caution and a lot of common sense. Be aware while traveling that is it possible to purchase a bottle of water that has opened, used then re-filled with water from questionable sources or labels that are phoney. Make your own personal judgement as to risk you wish to take. It is different for each person. I am once-bitten twice-shy about getting sick, so perhaps I am more aggressive to protect it than others. Someone asked if the bottle water looked like the picture sent. I don't remember. Sorry.