The topside of your bench is cleaned by water flow from the shower. Soap and grime can accumulate on the underside and in nooks and crannies, attracting mold and mildew. While unsightly, this will not affect the teak. To clean, use a soft bristle brush to gently scrub the teak with the grain. Rinse well with fresh water and let it air dry. To avoid grime or mildew, please ensure the teak regularly dries thoroughly. This is especially important in areas with little or no air circulation, such as enclosed shower stalls.