 The capsules incubate for about 3 weeks , depending on temperature . In warmer Indonesia , the incubation period was recorded to be only 15 to 16 days , while in Thailand it takes around 20 to 22 days . They gradually enlarge by absorbing water , reaching around 82 @.@ 4 mm ( 3 @.@ 24 in ) in length and 14 @.@ 6 mm ( 0 @.@ 57 in ) in width . Unfertilised eggs remain milky white and do not develop further . Fertilised eggs undergo cell division reaching a diameter of 16 mm ( 0 @.@ 63 in ) with the developing embryo at 11 mm ( 0 @.@ 43 in ) on the day before hatching . Upon hatching , the paralarvae are 6 mm ( 0 @.@ 24 in ) in mantle length ( excluding tentacles ) , with fully functioning fins and ink sacs . They resemble miniature adults and are already strong swimmers . They exhibit schooling behaviour two weeks after hatching . 
