An illumination system and method configured for mitigating a growth dip and as a consequence enhancing the growth of aquatic animals in a volume of water is disclosed. The illumination system comprises at least one light source (110) comprising at least one light emitting diode arranged to emit light to the volume of water and at least one light driver (120) arranged to drive the at least one light source. The illumination system also comprises a controller (140) that is adapted to provide control signals to the light driver to increase a light intensity level of the light emitted from the at least one light source from a first light intensity level (II) to a second light intensity level (l2) over a time period (T) of at least one day to two weeks, preferably at least two days to two weeks.
