Every year, when arriving at Liuchiiu, Black Tide divides into two currents flowing along both sides of the island. In addition, the water around the island is clean. Therefore, it is very suitable for net-cage fish farming. For years, the islanders raise grouper, cobia and greater amberjack by means of net-cage fish farming and export them to Japan. Differing from the traditional fish farming, the fish farm becomes one of the tourist attractions on the island.