Review: Abdel Rahman El Gamal (Founder of the website)
The inserted picture was taken in a marine hatchery in Italy in which gilthead seabream and European seabass are reproduced. The simple devices shown on the water surface of the tank are skimmers which trap oil originating from rotifers being fed an enrichment diet. The inflation of swim bladder of the larvae of marine fish is crucial to their wellbeing and survival. Fish larvae have to gulp air to inflate their swim bladders. The existence of oily layer as well as debris on water surface would interfere with the inflation process and its consequences such as negative buoyancy, abnormal swimming, reduced feeding and hence slower growth or even mortality. The surface skimmers shown in the picture trap the grease by blowing air at low pressure tangentially to water surface. Skimmers are periodically cleaned several times per day using a soft paper foil. This process continues for several days during which the inflation of swim bladders takes place.