Having worked in the water industry (but for industrial use high purity water), I can offer this one piece of extremely important advice. If anyone ever offers you High Purity, Reverse Osmosis, De-ionized water; run the fuck away. Seriously. Drinking that stuff for a long enough period of time can kill you, or at least make you severely ill.
RO/DI water that has been filtered by a good system can strip almost everything except two hydrogens and an oxygen from the water; leaving it with a conductivity of nearly zero. Theoretically (and this has been tested at some labs) if you're wearing a clean suit and standing in a pool of RO/DI water and someone drops a high voltage power line in; you'll be fine. There is nothing left in the water to conduct electricity. Companies like Intel and AMD use this stuff to wash circuit boards after the soldering process is completed.
Drinking it will strip the nutrients out of your body and leave you more dehydrated that you were before you drank it.
The company that I worked for actually use to service Boeing, and one day our techs walked in to one of the system locations on the Boeing campus in South Seattle to find that the system had disappeared (and we're talking several 4 foot tall resin tanks and a carbon tank plus all of the piping and tubing, not a small thing). They hunted around for it, called back to our service desk, got Boeing on the phone, and were finally told that it had been moved to a different office (which totally broke their contract, but that's neither here nor there). The techs got to the new location and the people in that location were using the system to run a drinking fountain and a coffee pot. The techs had to pull the system out and take everything back to the shop because it's not safe to drink. Idiot engineers.