One of the best ways to improve your coffee at home is to use the right water.
The Global Customized Water Perfect Cup Home Kit lets you treat distilled or reverse-osmosis water at home to perfectly emulate the water quality recommended by the Specialty Coffee Association and used by the best coffee houses in the world without the need for an expensive filtration system.
From the manufacturer:
"Water is often the most overlooked ingredient in the home coffee market, until now. Our Formula consists of two small bottles, Part A and Part B. When these two parts are mixed together with a gallon of distilled or reverse osmosis water, a consumer creates the same great taste they have come to enjoy from their favorite retail coffee or tea store. Enjoy the highest quality beverage any time, or anywhere.
This 30ml kit will make 238 - 9oz cups of water."