A vessel is approaching a deep-sea fish farm off the shore of Lianjiang county, Fujian province. By HUMEIDONG/CHINA DAILY

Three kilometers off the coast of Lianjiang county, Fujian province, stands a $2.5 million worth deep-sea farming platform, where traditional coastal aquaculture is not feasible.

Ten others loom in the waters nearby.

At the center of each platform is a horizontal octagonal cylinder, lying semi-submerged under water, with its sides covered with nets.

"More than 200,000 croakers are raised inside," said Lu Tongfeng, general manager of Fujian Xinmao Fishery Development Co, which owns the platform.

"The cylinder rotates regularly, so that algae and barnacles do not clog the nets and suffocate the fish inside," he explained. "It can also withstand strong typhoon."