The temporal and spatial behavior of the K I 7699 line profile is investigated. In particular, the asymmetries of the line profile at several residual intensities have been measured using the bisector method. Similar shapes are found in the bisector of the mean line profile as those obtained before for different positions on the solar disk. However, the strong variations of the bisector found with time and geometry of input aperture warns against the use of the mean or integrated profiles (either in time or space). Moreover, an anticorrelation is found between the asymmetry in the line profile at different residual intensities and the shift, found as the distance to a terrestrial line, for any position observed on the solar disk. No limb effect for this line is found, within errors.