HDPE cage technology: The key to Khanh Hoa’s offshore mariculture

On October 10, in Nha Trang ward, the National Agricultural Extension Center (NAEC), in collaboration with the Khanh Hoa Department of Agriculture and Environment, organized the forum Agricultural Extension @ Agriculture with the theme “Solutions for developing climate-resilient mariculture in the south-central coastal provinces.”

Mariculture as a vital pillar of the marine economy

According to Hoang Van Hong, Deputy Director of the National Agricultural Extension Center, the fisheries sector has identified mariculture as a key pillar in Vietnam’s Fisheries Sector Development Strategy to 2030, with a vision toward 2045. The goal is to develop mariculture into a major economic industry in response to new development requirements.

The agricultural sector's goals include 300,000 ha of mariculture nationwide by 2030, 12 million m³ of cage volume, 1.45 million tons of production, and an export value of USD 1.8 - 2 billion per year. To achieve these goals, developing high-tech, modern mariculture in key provinces such as Khanh Hoa and Quang Ninh will create strong momentum for Viet Nam’s mariculture industry.

Nguyen Trong Chanh, Deputy Director of the Khanh Hoa Department of Agriculture and Environment, said, “Khanh Hoa, a south-central coastal province with a nearly 500 km shoreline and many sheltered bays and lagoons, has favorable conditions for developing marine aquaculture.”

The aquaculture sector plays a vital role in Khanh Hoa’s socio-economic development, creating jobs and increasing income for coastal communities. The province’s annual fisheries output exceeds 32,000 tons, with mariculture accounting for nearly 50% of total production and contributing significantly to its seafood export value.

According to the Fisheries and Fisheries Surveillance Department, by the end of 2024, marine cage farming volume reached 9.7 million m³, up 38.6% compared to 2020 (an average annual growth rate of 8.7%), with 58,000 hectares of mollusk farming. Marine aquaculture output reached 832,000 tons, up 38.7% from 2020. Major farmed species include marine fish, lobsters, and mollusks, concentrated mainly in Khanh Hoa, Dak Lak, Quang Ninh, Hai Phong, Ho Chi Minh City, and An Giang.

HDPE technology is the answer

NAEC Deputy Director Hoang Van Hong emphasized the urgent task of finding sustainable solutions for developing the marine economy in the context of negative impacts due to climate change and extreme weather phenomena. The Ministry of Agriculture and Environment is paying close attention and taking strong measures to enhance marine farming technologies, aiming to protect the environment, develop the economy, and meet illegal, unreported, and unregulated (IUU) fishing control requirements.

A core solution proposed by the National Agricultural Extension Center is to transition from traditional wooden cages to resilient cages made of materials such as high-density polyethylene (HDPE). Agricultural extension models applying HDPE cage technology have proven to deliver outstanding economic efficiency.

A report presented at the forum shows that the NAEC’s model of farming cobia (Rachycentron canadum) in HDPE cages in Quang Ngai and Khanh Hoa achieved an average profit of nearly VND 200 million per cage after nine months. Considering the total farm scale of 2,700 m³, this is a 308% increase compared to traditional wooden cages. Golden pompano models using HDPE cages totaling 4,000 m³ in Quang Ninh and Khanh Hoa also showed 13% higher productivity than farms outside ò the model.

Hoang Van Hoi, Director of the Aquaculture Services and Technology Co., Ltd., who has 17 years of experience in the field, shared deeper insights on HDPE cage technology at the forum. The product results from patented innovations and practical solutions, now widely adopted by farmers in Khanh Hoa, Thanh Hoa, and many other provinces.

HDPE cages come in circular or square designs, suitable for marine, river, and reservoir farming. Each cage is customized for local conditions and tested to withstand waves and winds up to level 12 storms. Khanh Hoa province has decided to include these cages in its pilot high-tech mariculture project.

Anticipating the mariculture industrial wave

To implement the national Marine Aquaculture Development Project approved by the Prime Minister under Decision No. 1664, and particularly the Politburo’s Resolution No. 09 on the construction and development of Khanh Hoa Province toward 2030, Khanh Hoa has formulated a pilot project for high-tech mariculture, approved by the Prime Minister on January 24, 2025.

Information from the Khanh Hoa Agricultural Service Center shows that 27 fishermen have so far participated in installing and launching new cages, including 50 round cages and 12 square cage clusters, forming concentrated industrial farming clusters.

Many businesses, individuals, and households have registered and begun production in high-tech farming areas. They focus mainly on marine fish and use new materials such as HDPE and FRP. The use of automatic environmental monitoring devices, feeding systems, and cage surveillance cameras has helped reduce costs, minimize disaster risks, and improve disease control.

Vu Khac Muoi, a pioneering fisherman in high-tech mariculture in Dam Bay (Nha Trang Ward), is a clear example of successful transition. He confirms the exceptional resilience of HDPE cages in the face of natural disasters. He has been licensed to farm golden pompano and cobia over 1,000 m² of water surface, with an expected yield of 30 tons per year. The experience of Muoi and other pioneers is inspiring fellow farmers, promoting technology expansion, and thereby building a stable, high-quality mariculture value chain.