Yes, reverse osmosis water with a lack of minerals tastes different from other types of water. That’s because it is almost totally devoid of all dissolved inorganic solids, including salts, minerals, and contaminants. Some people describe the flavor as "flat" and some believe it makes beverages like coffee taste somewhat bitter. But, taste is very subjective and other people notice little difference between reverse osmosis water and that produced by other filtration methods. If the flavor doesn’t appeal to you, a simple solution is to add a calcium cartridge to the water or choose a reverse osmosis system with an alkalinization stage. This helps neutralize the acidity caused by the decreased PH level.