Construction of two massive intelligent deep-sea aquaculture platforms named Yunhai, or "farming the sea", will be completed by the end of this year in the waters of Fuzhou, adding to the city's existing fleet and bringing the total number of smart platforms in the marine-resource-rich capital of Fujian province to 15 units.

Data from the Fuzhou Ocean and Fisheries Bureau shows that the city's smart platforms encompass 270,000 cubic meters of water, yielding more than 2,200 metric tons of seafood annually with an output value of 300 million yuan ($44.25 million), placing Fuzhou among the national leaders in deep-sea aquaculture.

In recent years, a fleet of advanced deep-sea platforms, dubbed the "Iron Men of the Sea", has been intensively deployed across Fuzhou to cultivate high-quality seafood such as large yellow croakers and abalone. These platforms use automated feeding and monitoring systems, significantly reducing labor while supporting the development of modern marine ranches.

Among the deployed fleet, platforms named Qiandong, which hold nearly 50 patents and copyrights, are scaling up commercial large yellow croaker production in Dinghai Bay, Lianjiang county of Fuzhou.

Featuring 20,000 cu m of breeding water each, the zero-carbon system integrates four core subsystems, including an automatic rotating cage powered by complementary solar and wind energy, and operates nearly 20 smart sensors for digital management.

Li Xiaoping, assistant to the chairman of Qiandong Marine Granary, said the equipment features a 360-degree floating cage that can withstand super typhoons above wind scale 16+, requiring only one or two crew members for routine maintenance.

"The cage integrates automated rotating and lifting technologies, turning above the water level every three days for sun-drying to clear biofouling," Li said. "This effectively resolves historical harvesting and biofouling bottlenecks faced by earlier models, eliminating the need for frequent service vessels."

The upcoming Yunhai platforms represent a 130 million yuan investment with a combined capacity of 170,000 cu m, scheduled for completion by the end of this year.

Chen Jinwen, a technical employee of Marine Granary (Fujian) Technology Co, said the Yunhai platforms achieve an 80 percent digitization rate across the entire production life cycle, featuring 10 feed silos with a capacity of 10 tons each for smartphone-controlled feeding.

"Because open-ocean currents are rapid, the high activity level of the fish ensures superior meat quality that closely resembles wild-caught species," Chen said.

Chen added that local government support, including the provision of sea areas free of charge, has boosted industry confidence. "Moving forward, we will invite traditional local fish farmers to become shareholders to help manage the assets," he said.

"This initiative will help traditional fishermen transition into shore-based fishermen, managing advanced marine ranches directly from their smartphones," Chen said.

According to the Fujian provincial government work report, the province's deep-sea aquaculture scale ranks first in the country. Fujian is deepening its "Maritime Fujian" initiative to push aquaculture further into the deep sea.

Provincial leaders attended a meeting in Fuzhou on Thursday to discuss accelerating the development of distinctive rural and agricultural industries, transforming agriculture into a modernized sector, and further improving farmers' livelihoods.

Contact the writers at zhangyi1@chinadaily.com.cn