Micro-fouling (slime, algae, etc.) and macro-fouling (barnacles, clams, hydroids, mussels, etc.) organisms in the marine environment find ideal growing conditions in ships' on-board cooling circuits, particularly in titanium systems. Temperature, salinity, low flow and the presence of oxygen promote the fouling phenomenon. Hypochlorite (HOCl) is acknowledged as being the best anti-fouling agent against both micro- and macro-fouling. Our chlorinators use an electrolytic cell to produce HOCl directly from sea water. The system is installed in a machinery space near a sea water intake, and the anti-fouling agent is injected into the sea chest; from there it is dispersed throughout the sea water system.