An ice maker for forming ice, the ice maker comprising: (i) a refrigeration system comprising a compressor, a condenser, an evaporator, and a freeze plate thermally coupled to the evaporator, wherein the compressor, condenser and evaporator are in fluid communication by one or more refrigerant lines (28a, 28b, 28c, 28d); (ii) a water system for supplying water to the freeze plate, the water system comprising a sump below the freeze plate, wherein the sump comprises a main water reservoir for holding water and a sanitizer reservoir for holding a sanitizer, a water distributor above the freeze plate, and a water pump, wherein the water pump is in fluid communication with the sump and the water distributor by a water line, the water system further comprising a water supply line and a water inlet valve in fluid communication therewith wherein the water inlet valve is adapted to supply water to the sump; and (iii) a water level sensor adapted to determine the water level in the sump; and (iv) a controller adapted to control the ice maker in response to the water level in the sump measured by the water level sensor, wherein the controller is adapted to: (a) open the water inlet valve to fill the main water reservoir with water to an ice making water level during an ice making cycle; (b) open the water inlet valve to fill the main water reservoir with water to a descale water level during a descale portion of a descale and sanitize process; and (c) open the water inlet valve to fill the main water reservoir with water to a sanitize water level during a sanitize portion of the descale and sanitize process, wherein the sanitize water level is above the descale water level, and wherein when the sanitize water level is reached the sanitizer in the sanitizer reservoir is adapted to enter the main water reservoir. (i) a refrigeration system comprising a compressor, a condenser, an evaporator, and a freeze plate thermally coupled to the evaporator, wherein the compressor, condenser and evaporator are in fluid communication by one or more refrigerant lines (28a, 28b, 28c, 28d); (ii) a water system for supplying water to the freeze plate, the water system comprising a sump below the freeze plate, wherein the sump comprises a main water reservoir for holding water and a sanitizer reservoir for holding a sanitizer, a water distributor above the freeze plate, and a water pump, wherein the water pump is in fluid communication with the sump and the water distributor by a water line, the water system further comprising a water supply line and a water inlet valve in fluid communication therewith wherein the water inlet valve is adapted to supply water to the sump; and (iii) a water level sensor adapted to determine the water level in the sump; and (iv) a controller adapted to control the ice maker in response to the water level in the sump measured by the water level sensor, wherein the controller is adapted to: (a) open the water inlet valve to fill the main water reservoir with water to an ice making water level during an ice making cycle; (b) open the water inlet valve to fill the main water reservoir with water to a descale water level during a descale portion of a descale and sanitize process; and (c) open the water inlet valve to fill the main water reservoir with water to a sanitize water level during a sanitize portion of the descale and sanitize process, wherein the sanitize water level is above the descale water level, and wherein when the sanitize water level is reached the sanitizer in the sanitizer reservoir is adapted to enter the main water reservoir. (a) open the water inlet valve to fill the main water reservoir with water to an ice making water level during an ice making cycle; (b) open the water inlet valve to fill the main water reservoir with water to a descale water level during a descale portion of a descale and sanitize process; and (c) open the water inlet valve to fill the main water reservoir with water to a sanitize water level during a sanitize portion of the descale and sanitize process, wherein the sanitize water level is above the descale water level, and wherein when the sanitize water level is reached the sanitizer in the sanitizer reservoir is adapted to enter the main water reservoir.