This study explores the economic viability and adoption of the tube net method for seaweed
farming, particularly for Kappaphycus alvarezii cultivation, along the southeastern coast of
Tamil Nadu, India. The research examines the financial feasibility, operational costs, and
socio-economic characteristics of coastal farmers engaged in seaweed cultivation using this
method. Primary data was collected from 120 farmers in Mandapam taluk, focusing on
investment, operational expenses, yields, and labor requirements. The results show that the
method offers a promising alternative to traditional bamboo raft farming, with substantial
profitability potential. The system yields an estimated 39,000 kg of fresh seaweed per year,
generating a gross sales income of ₹3,90,000 annually, with net earnings of ₹1,56,755 per
year for a 25-raft unit. The benefit-cost ratio of 1.67 indicates a high return on investment,
and the system’s low break-even price of ₹59.81 per kilogram demonstrates its financial
resilience. The modular design allows for scalability, making it accessible to small-scale
farmers with minimal financial barriers. The study concludes that despite its advantages, the
tube net method faces some challenges like limited awareness, high initial costs, and regional
ecological constraints affect adoption. The method remains sustainable, profitable, and
community-friendly, aligning with government livelihood schemes and blue economy goals.