Anti-fouling lighting system (1) for preventing or reducing bio fouling on a fouling surface (1201) of an object (1200), by providing an anti-fouling light (211) via an optical medium (220) to said fouling surface, the anti-fouling lighting (1) system comprising: (a) a lighting module (200) comprising (i) a light source (210) configured to generate an anti-fouling light (211), and (ii) said optical medium (220) configured to receive at least part of the anti-fouling light (211), the optical medium (220) comprising an emission surface (222) configured to provide at least part of said anti-fouling light (211)； and (b) a control system (300) configured to control an intensity of the anti-fouling light (211) as function of one or more of (i) a feedback signal related to a biofouling risk and (ii) a timer for time-based varying the intensity of the anti-fouling light (211).
