An apparatus and method for smelting has a smelting pot for containing electrolyte, alumina and a layer of liquid aluminum. A wall in the form of one or more TiB2 or alumina plates extends from the bottom of the pot to a height exceeding the height of the liquid aluminum layer formed in the bottom of the smelting pot during smelting. The wall partitions the bottom of the pot and impedes movement of the aluminum under the influence of MHD forces, diminishing the maximum crest height of waves in the aluminum and allowing a reduction in the ACD to reduce electrical resistance and power consumption. The wall may equal or exceed the height of the anode and may, when conductive, act as a cathode, drawing a horizontal current. The wall may be composed of alumina, e.g., in the form of blocks, undergoing electrolytic reduction and being replaced periodically.