A printhead assembly, comprising: a) an ink cartridge body; b) an ink reservoir disposed within the ink cartridge body and adapted to receive and contain ink; c) a filter (20, 30) disposed adjacent the ink reservoir to filter ink supplied from the ink reservoir as the ink passes through the filter; d) a printhead chip provided on the ink cartridge body and in fluid communication with the ink reservoir so as to receive the filtered ink for ejection of the ink onto a print medium; e) an ink filter tower disposed between the filter and the printhead chip, the ink filter tower comprising: f) an ink entrance passage that receives the filtered ink; f1) a chamber that holds the filtered ink received through the ink entrance passage; f2) a plurality of extending elements formed by pillars (81, 82, 83) attached at the bottom of the chamber disposed within the chamber, the filtered ink passing through the chamber and around the plurality of extending elements, wherein the extending elements are spaced apart from, and are substantially parallel to, one another; f3) a plurality of trenches (89, 90) disposed within the chamber, wherein the plurality of trenches are defined by the spaces between the extending elements; and f4) a free-floating member formed as a slider free floating in the sense that it is not physically connected to other elements in the tower and positioned within the ink filter tower that agitates the filtered ink within the ink filter tower, the free-floating member comprising a bridging member and a plurality of shafts (84, 85, 86) protruding from the bridging member substantially parallel to one another, the shafts (84, 85) situated within the trenches (89,90) between the extending elements (81, 82, 83) with one shaft arranged in the chamber outside the trenches adjacent to one extending element such that the free-floating member is slidable with the ink filter tower in an opposite direction to a direction of motion of the printhead assembly to agitate the filtered ink within the ink filter tower. a) an ink cartridge body; b) an ink reservoir disposed within the ink cartridge body and adapted to receive and contain ink; c) a filter (20, 30) disposed adjacent the ink reservoir to filter ink supplied from the ink reservoir as the ink passes through the filter; d) a printhead chip provided on the ink cartridge body and in fluid communication with the ink reservoir so as to receive the filtered ink for ejection of the ink onto a print medium; e) an ink filter tower disposed between the filter and the printhead chip, the ink filter tower comprising: f) an ink entrance passage that receives the filtered ink; f1) a chamber that holds the filtered ink received through the ink entrance passage; f2) a plurality of extending elements formed by pillars (81, 82, 83) attached at the bottom of the chamber disposed within the chamber, the filtered ink passing through the chamber and around the plurality of extending elements, wherein the extending elements are spaced apart from, and are substantially parallel to, one another; f3) a plurality of trenches (89, 90) disposed within the chamber, wherein the plurality of trenches are defined by the spaces between the extending elements; and f4) a free-floating member formed as a slider free floating in the sense that it is not physically connected to other elements in the tower and positioned within the ink filter tower that agitates the filtered ink within the ink filter tower, the free-floating member comprising a bridging member and a plurality of shafts (84, 85, 86) protruding from the bridging member substantially parallel to one another, the shafts (84, 85) situated within the trenches (89,90) between the extending elements (81, 82, 83) with one shaft arranged in the chamber outside the trenches adjacent to one extending element such that the free-floating member is slidable with the ink filter tower in an opposite direction to a direction of motion of the printhead assembly to agitate the filtered ink within the ink filter tower. f1) a chamber that holds the filtered ink received through the ink entrance passage; f2) a plurality of extending elements formed by pillars (81, 82, 83) attached at the bottom of the chamber disposed within the chamber, the filtered ink passing through the chamber and around the plurality of extending elements, wherein the extending elements are spaced apart from, and are substantially parallel to, one another; f3) a plurality of trenches (89, 90) disposed within the chamber, wherein the plurality of trenches are defined by the spaces between the extending elements; and f4) a free-floating member formed as a slider free floating in the sense that it is not physically connected to other elements in the tower and positioned within the ink filter tower that agitates the filtered ink within the ink filter tower, the free-floating member comprising a bridging member and a plurality of shafts (84, 85, 86) protruding from the bridging member substantially parallel to one another, the shafts (84, 85) situated within the trenches (89,90) between the extending elements (81, 82, 83) with one shaft arranged in the chamber outside the trenches adjacent to one extending element such that the free-floating member is slidable with the ink filter tower in an opposite direction to a direction of motion of the printhead assembly to agitate the filtered ink within the ink filter tower.