Hand-wash; dry immediately with soft cloth. Refresh water daily.
Avoid using steel wool, dishwasher, steel scouring pads or harsh detergents.
Clean bowl before using with a lemon cut in half with a little salt rubbing in circular motions, rinse with water, and dry completely. Continue this process occasionally during continued use.
Copper will develop a rich patina over time. This will not affect the bowl's performance. To keep the exterior looking new, use a copper polish or a combination of lemon and salt.