A cost and benefit analysis of Nile tilapia culture in biofloc technology, the environmental friendly system: the case of selected farm in Chiang Mai, Thailand

This study aimed to investigate the cost and benefit as well as other economic analysis of Nile tilapia culture in the biofloc system. The data derived from the selected study area where was the initial farm rearing in biofloc system in Chiang Mai province, Thailand. The study revealed that the 50 fingerings m-3 were released in sphere-shape polyethylene ponds (9 m of diameter x 1.20 m height), and raised for 5 months to reach the harvest size (500-600 g). The fish yield was about 1,500 kg/pond or 25 kg m-3. Total production cost was 101,988 Baht, divided into total fixed cost 13,656 Baht/pond (13.39%) and total variable cost 88,333 Baht/pond (86.61%). Fish feed cost was the highest at price (58.34%). The fish price was determined at 85 Baht/kg, 15% increasing from Nile tilapia common culture. Because they were cultured in the chemical and antibiotic-free system that produced the income to 121,125 Baht/pond and would receive net profit at 19,137 Baht/pond on average from 1,425 kg/pond with 95% of survival rate. Total income was 484,500 Baht/crop and total net profit was 76,549 Baht/crop. In other words, the net profit per kg was 13 Baht. The benefit and cost ratio (B/C ratio) was 1.19, and the net present value (NPV) assessment was 1.43 million Baht, which means worthiness to invest. The expected returns of this project or Internal rate of return; IRR was 45%, which was a greater ratio than the minimum expected returns (15% of the interest rate of return calculation). The payback period was 7.14 years, which indicated that the investors had to run this business for 7 years and one and a half months to recover their investment money. Consequently, the business has a favorable prospect, and the biofloc system for the culture of tilapia is applicable for fish farmers.