title: A closed marine culture system for rearing Octopus joubini and other large-egged benthic octopods.
abstract: The system consists of 2 adjoining 150 litre aquaria, one functioning as the water-conditioning tank and the other as the principal rearing tank. Water quality remained high with biological and mechanical filtration, physical adsorption and ultraviolet-light disinfection taking place exclusively in the conditioning tank. The pH ranged from 7.58 to 8.00 and ammonia and nitrite levels never exceeded 0.004 mg/l and 0.198 mg/l, respectively. Nitrate levels were maintained at 40 mg/l or less with no adverse affects. Adult octopuses readily mated and females produced 50-150 eggs, with 95% hatching success. When fed small liver crabs, the octopus hatchlings were reared to sexual maturity either in groups or individually in about 120-150 days. Growth rates (4% bodyweight/day) and food conversion efficiences (30-40%) were as high as those obtained in open systems by previous workers.
mesh_terms: D000641:Ammonia / Q000032:analysis; D000818:Animals; D006799:Housing, Animal; D006863:Hydrogen-Ion Concentration; D049831:Octopodiformes / Q000254:growth & development*; D014867:Water / Q000032:analysis
chemical_list: D014867:Water; D000641:Ammonia