Abstract: An ionically resistive ionically permeable element for use in an electroplating apparatus includes ribs to tailor hydrodynamic environment proximate a substrate during electroplating. In one implementation, the ionically resistive ionically permeable element includes a channeled portion that is at least coextensive with a plating face of the substrate, and a plurality of ribs extending from the substrate-facing surface of the channeled portion towards the substrate. Ribs include a first plurality of ribs of full maximum height and a second plurality of ribs of smaller maximum height than the full maximum height. In one implementation the ribs of smaller maximum height are disposed such that the maximum height of the ribs gradually increases in a direction from one edge of the element to the center of the element.