In one embodiment, a method for introducing ink into an ink cartridge includes introducing ink into an ink holding chamber through ink ejection nozzles and, simultaneously with introducing ink into the ink holding chamber through the ink ejection nozzles, introducing ink into the ink holding chamber through an opening other than the ink ejection nozzles or applying a negative pressure at a first opening to the ink holding chamber and applying a positive pressure at a second opening to the ink holding chamber. In another embodiment, a method includes performing a primary operation on an ink holding chamber by introducing ink into the ink holding chamber through ink ejection nozzles and performing a secondary operation on the ink holding chamber to increase the flow of ink to a distal part of the ink holding chamber relative to the flow of ink to a proximal part of the ink holding chamber.