Agriculture in the hills has limitations with a number of factors such as small land holdings, dependency on rain for irrigation and temperate climate. Mid hills suffers from the paradoxical situation of being classed as both 'high potential' in rainy season but 'water scarcity' in summer and winter. These factors force the human resource to migrate from the hill to plain areas for earning their livelihood resulted in barren lands. In this context, fish farming with vegetable production is an option of earning to the rural people of hills especially farm women. Polythene lined pond provide facility for rainwater harvesting in uplands and its storage for the multiple use such as fish farming and horticulture. These polytanks are also provided increasing water temperature besides the control of water seepage. Polyculture of exotic carp is common practice in mid hill condition, which is a supplementary feeding based practice. Silver carp and common carp do not grow well in this polyculture system due to low thermal regime, less plankton in pond water. Only grass carp perform better growth even in winter season. Feeding cost to growing exotic carps is also not affordable to the farmers. Hence, an attempt has been made to evaluate the growth of grass carp in three culture systems such as traditional practice of Polyculture of 3 exotic carps such as silver carp (Hypophthalmichthys molitrix), grass carp (Ctenopharyngodon idella) and common carp (Cyprinus carpio var. communis), polyculture of grass carp with common carp and monoculture of grass carp in polytanks located in mid altitudinal area of Kumaon hills (950-2000 msl) coupled with impact on pond water qualities. In 9 months field study, data revealed that the mean weights and daily weight gains of grass carp in monoculture and polyculture with 2 species were significantly higher than those in polyculture of 3 species (control). A significant difference was observed with 22% increase in monoculture and 37% increase in polyculture of 2 species in total production over the control units. Water quality parameters also reflected a conducive environment for the growth and survival in both the treatments. Economically, 24-37% increase in net income with better size of harvested fish was observed in treatments over the traditional practice. Fresh azolla feeding was adopted to feed the grass carp which has been reduced 24% feeding cost. Hence, polyculture of grass carp with common carp is an economic, technically feasible and eco friendly practice for the mid altitudinal area in hills.