The intensive hikeponds in the Pearl River Delta are taken to establish a water quality model for pond farming. The results of model verification indicate that the simulation of the model fits the real situation well and it can be used as a research tool for pond aquaculture ecosystem or as a decision support tool for the management of pond farming. The model established is used to research main factors affecting the water quality and the carrying capacity of farming ponds. Results show that DO is generated mainly from phytoplankton photosynthesis and artificial oxygen enhancement

and consumed mainly by fish respiration. DO contents are influenced by various factors. TAN and SRP are generated mainly from fish metabolization and consumed mainly by absorption of phytoplanktons. They change much slowly compared with DO. The farming capacity of the farming ponds is influenced by many factors

including internal factors such as feed digestion and utilization and external factors such as the DO level and the TAN accumulation. The farming capacity of the mainly farmed fish increases with the increase of feed digestion rate and is restricted by the lack of DO and the high TAN concentration. The farming capacity of secondarily farmed fish increases with increasing availability of the heterotrophic feed caused by the decrease of digestion of feed for mainly farmed fish，and is restricted by the lack of DO. Mixed

rotational fishing model makes full exploitation of farming space

which can further extend the farming capacity in fish ponds.