alot of supermarkets around here do not sell bottled ro water, even by the gallon. However, read the water machine by the bottled water and see if it mentions a reverse osmosis membrane... Walmart has it most of the time, or if there is a meijers near you, they almost always have it. The Kroger right by me, like 1/16 mile used to have a machine, but the a-holes went hellen keller and re-arranged the store and got rid of it...