Quality Monosex Tilapia and African Catfish Fingerlings Jumbo Fish specializes in Tilapia (Oreochromis niloticus) and African Catfish (Claries Gariepinus) fingerling production. The production of the fingerlings is done in Recirculation Aquaculture System (RAS). The RAS system is specially designed to hatch many African Catfish and Tilapia eggs and maintains optimal conditions for the fry, fingerlings and Brood-stock.