 Juveniles of the species usually seek shelter and safety from predators within clusters of drifting seaweed . The adult thread @-@ sail filefish usually reside near the <unk> , where the depth is around 10 metres ( 33 feet ) . The fish migrate wholly in ocean waters ( " <unk> " ) between their feeding and spawning grounds , which can cover a range of over 100 kilometres ( 62 miles ) . The spawning season lasts from May to August . Juveniles under 5 centimetres ( 2 @.@ 0 inches ) inhabit shallow water and feed on small crustaceans , <unk> and algae . Adult fish are mostly solitary and live among the coral and <unk> . 
