Tank spawning of grass carp

Induced spawning of grass carp in indoor tanks without hand stripping of gametes is described. Circular tanks (1.83 m diameter) with biofiltration units were utilized for conditioning and spawning. This method was found to be successful and has several advantages over the dry-fertilization method: (1) preliminary ripening and spawning is conducted in small systems where the environment is controlled; (2) manpower requirements are reduced; (3) handling of brood fish is reduced, thereby minimizing mortalities; and (4) spawning occurs when the fish is physiologically ready, insuring good egg quality.