Copper Care The way to keep your copper sink in optimal condition i$ to keep it clean and dry. For basic cleaning, simply use a mild soap and water; other cleaners are not necessary. A good habit is to wipe the sink dry after each use, especially in hard water areas. For extra protection, products such as Renaissance Was may be applied to the copper surface periodically. These seals will help maintain the luster of the copper and provide batter water runoff.