Use of Wastewater Effluent from Striped Catfish (Pangasius Hypothalamus) Ponds for Integrated Rice-Fish Farming System

Cao Van Thich*, Chau Thi Da, Tran Thi Kim Tuyen, Thai Huynh Phuong Lan**, Nguyen Huu Yen Nhi and Do Tran Minh Luan*

Aquaculture Department of Faculty of Agriculture and Natural Resources, An Giang University, Vietnam,  *Aquaculture Department of Faculty of Agriculture and Natural Resources, An Giang University, Vietnam (Campus II- Chau Phu district);
**International Cooperation of Faculty of Agriculture and Natural Resources, An Giang University, Vietnam  

Abstract

A study was made of integrated fish and rice production using river water or waste water from catfish ponds to irrigate the rice. Nile tilapia were cultured in a  pond  (400 m²)  adjacent to the rice field which had 9 plots with a total area of 1800m².  The fish were fed with rice bran (2 times/week) and the natural nutrients generated from water from the river and the catfish ponds as well as from the   rice field. Three treatments were applied to the rice field: (1) normal rice culture with 120-46-30 (N-P₂O₅-K₂O) and using water from river (as control treatment); (2) rice cultivation with 80-32-30 (N-P₂O₅-K₂O) + 30kg K₂O/ha and using wastewater from striped catfish pond as nutrient input; and  (3) rice cultivation with 80-32-30 (N-P₂O₅-K₂O) and using wastewater from striped catfish pond as nutrient input. The rice yields were higher when waste water from the catfish ponds was used (Table 1). Profit was increased 29% in the combined rice-fish system compared with rice alone in the same total area. 

Key words: Economics, environment, fertilization, integration, pollution