Yield and nutrients leaf content of butterhead lettuce (Lactuca sativa) in response to fish nutrient solution in a small scale of aquaponic systems

Abstract

This study was conducted over 52 days to evaluate the potential of using the nutrient solution produced from different fish stocking densities on the yield and nutrients leaf content of lettuce cultivated in decoupled recircula-tion aquaponic systems (DRAPS). In this study, three stocking densities of tilapia were used 8, 10 and 12 kg m-3, respectively. The result showed the highest total yield 448 g m-2 was obtained at a low stocking density. Also, it has been showing that with an increased fish stocking density, the leaf nutrient content of butterhead lettuce for potassium, calcium, magnesium, sodium, iron and copper was increased. While for the nitrogen, phosphorus and manganese, the higher leaf content was obtained at lower stocking density. Considering the lettuce yield, leaf nutrient contents and nitrogen dynamics, the stocking density of 8 kg m⁻³ could be suggested as the ideal stocking density for DRAPS.