Using Wastewater From Fish Farming for Fertigation of Lettuce Crop

Abstract

This study aimed to explore the efficacy of utilizing wastewater from fish farming tanks for fertigating lettuce crops as an alternative to inappropriate disposal methods. A randomized block experimental design was employed in a 3 x 8 factorial scheme, comprising three treatments: two varying percentages of wastewater (50% and 100%), alongside a control treatment employing only well water, with eight replications each. The trial was conducted in a field under protected cultivation, within a low tunnel-type structure. Biometric parameters of the lettuce plants were analyzed, including stem diameter, plant height, stem length, head diameter, root length, leaf fresh matter, leaf dry matter, stem fresh matter, stem dry matter, root fresh matter, root dry matter, leaf count, fresh shoot mass, and commercial productivity. Significant results were observed with the application of 100% wastewater treatment up to 20 days after transplanting (DAT), particularly for the biometric variables: plant head diameter (average 37.4 cm) and leaf count (average 13.7 units) at 36 DAT, of crisp lettuce Grand Rapids loose leaf seedlings. The reuse of wastewater during the experiment showed promising potential in replacing chemical fertilizers throughout the crop cycle. This practice facilitates the repurposing of water from fish farming, providing farmers with an alternative income source during the fish development phase, and mitigates improper wastewater disposal.