Speaking of tap water, I only use filtered water at home for both their water dishes and water on their food. When traveling I use only bottled water. Depending on the water you use... if you look at the residue in the bowl, you would not be drinking that either... we have very hard water, reason for filtered. And when traveling, bottle is best so you don't have a change because elbrant is correct, water from one location to another varies.
Most all breeders will/do recommend boy/girl... While you can luck out with girl/girl if problems start it is very, very unlikely that they will get alone after that... and fights will flare up at anytime... males not so much. As we say, it works till it doesn't. I would suggest as a breeder that you go for a male pup in your situation