This study was aimed at knowing the technical and economic efficiency of fish culture in cage system for fish farmers in running the business to be able to increase their income. It was carried out in two phases; in which the first step yields the technical efficiency for the fish cage famers in Tondano Lake, Remboken district, Minahasa regency. The technical and economic efficiency was obtained through direct observations, interviews, and used Data Envelopment Analysis (DEA) method and business feasibility analysis. Data Envelope Analysis (DEA) Solver showed that only one of 15 fish farmers under fish net cage (FNC) culture system reached the best technical efficiency.
The FNC business with an investment of IDR 17, 336,000 will give a revenue of IDR 225,000,000/yr with net profit of IDR 135,786,000/yr, IRR of 783.26%, and BCR of 2.14. Feasibility analysis using a discount factor of 12% and time period of 10 years found NVP>0, BCR>1, and IRR>discount factors, meaning that the FNC business is feasible to run.