Comment by gwbas1c

It really depends an what you're doing. If you have a small aquarium, (5 or under gallons,) buying water instead of treating it yourself may be easier, and cheaper. (Aquarium chemicals aren't cheap.)

Personally, I've been tempted to bring water from my parent's house, because their water is loaded with copper, which makes it very hard for ick to spread. Unfortunately, my aquarium is far too large to make it practical to move water from their house to mine.