This disclosure relates to a separating a fluid having multiple phases during formation testing. For example, certain embodiments of the present disclosure relate to receiving contaminated formation fluid on a first flow line and separating a contamination (e.g., mud filtrate) from the formation fluid by diverting the relatively heavier and/or denser fluid (e.g., the mud filtrate) downward through a second flow line and diverting the relatively lighter and/or less dense fluid upward through a third flow line. In some embodiments, the third flow line is generally oriented upwards at a height that may facilitate the separation of the heavier fluid from the relatively lighter fluid based on gravity and/or pumps.