Two fingerling sizes of grass carp were grown to market size in ponds using the ASA 80:20 production model and a soy-based diet. Fish were stocked at 600 grass carp per mu together with 100 silver carp per mu. Fingerlings of sizes 70 g and 100 g grew respectively to 797 g and 827 g in 178 days of feeding. Net production for the three, 100-g fingerling ponds averaged 438 kg/mu of grass carp and 113 kg/mu of silver carp. Net production for the three, 70-g fingerling ponds averaged 429 kg/mu of grass carp and 108 kg/mu of silver carp. The 100-g fingerlings reached a target market size of 750 g in 156 days, while the 70-g fingerlings reached 750 g in 165 days. FCR with the ASA all- plant protein, soy-based diet was 1.22 for the 70-g fingerlings and 1.19 for the 100-g fingerlings. Use of this diet in the extruded, floating form allowed the Xu Xing Zhang farm manager to closely monitor fish feeding performance and fish health and prevented over-feeding of fish and wasting of feed. Net economic return and return on investment were RMB 804/mu and 24% for the 70-g fingerling treatment, and RMB 449/mu and 11.7% for the 100-g fingerling treatment.