A microfluid ejection system includes a fluid path having proximate and distal ends, the proximate end having an inlet to receive fluid from a fluid supply, a vacuum chamber for suctioning of air from both the proximate and distal ends of the fluid path, and a pre-ejection chamber disposed in the fluid path between a proximate end and a distal end. The pre-ejection chamber includes a ceiling inclined upward toward each of the proximate and distal ends from a low point to direct air toward either the proximate or distal end for suctioning from the pre-ejection chamber. The microfluid system further includes a first and second air chambers disposed respectively at the proximate and distal ends of the fluid path to receive and direct air to the vacuum chamber.