ABSTRACT A DEVICE AND A METHOD FOR REDUCING THE NUMBER OF EXTE¬RIOR PARASITES ON FISH A device for reducing the number of exterior parasites on fish, comprising a hollow cylindrical filter member having an inlet and an outlet, the circumference of the inlet and/or outlet being provided with a nozzle, wherein the nozzle comprises a substantially annular slit along the circum¬ference of the inlet and/or outlet for ejecting a fluid towards the interior of the cylindrical filter.
