Boxcoolers are in direct contact with the water the ship sails in. The biodiversity in coastal regions and estuarine conditions can be responsible for the growth of biological fouling, also on the boxcoolers. To prevent this marine growth from obstructing the free flow of water around the coolers, so-called marine growth prevention systems can be installed. An ICAF (Impressed Current Antifouling) system provides an unattractive environment for marine fouling. Unfortunately this system generates copper ions. Blokland has, recently, invested heavily in the development of an advanced ultrasonic system (GreenSonic), which is capable of preventing a substantial amount of marine growth to settle on the coolers. Under specific conditions, especially where in coastal area’s the seabottom is disturbed by dredging operations, this ultrasound technology, might not be enough to keep boxcoolers sufficiently free from fouling. Especially for these conditions the GreenSonic hybrid system was developed, combining both technologies, with the advantage of reducing the amount of copper being dissolved, substantially.