When you first use a new countertop reverse osmosis water filter, the taste of the water may change. This is mainly due to the activated carbon dust in the new filter. The activated carbon filter usually needs to be rinsed before the first use to remove impurities and carbon dust to prevent them from affecting the taste of the water. In addition, the taste of purified water may also change due to installation or configuration problems, such as loose interfaces that allow air to mix into the system. In addition, as chlorine and other chemicals are removed from tap water, your taste may take time to adjust to the new water quality. Make sure to follow the instructions and contact the manufacturer or professional service if necessary to ensure that the water purifier is operating correctly to ensure water quality and taste.