Analysis of Fish and Water Spinach Growth in an Aquaponic System Based on the Utilization of Ablution Wastewater

Abstract

This study aims to analyze the growth of fish and kale plants in an aquaponic system based on the utilization of ablution wastewater as an effort to manage water sustainably in an Islamic boarding school environment. The study was conducted at the As-Salafiyyah Asy-Syafi’iyyah Islamic Boarding School, Tambakberas Barat, Jombang, East Java from August to October 2025. The types of fish used include Patin (Iridescent shark), Mujair (Tilapia), Gurami (Gourami), and Lele (Catfish), while the plants cultivated are kale (Ipomoea aquatica). Fish growth parameters were measured using Daily Weight Gain (DWG) and Specific Growth Rate (SGR), while plant growth was analyzed through Crop Growth Rate (CGR). The results showed that Mujair (Tilapia) fish had the best growth with the highest DWG of 1.71 g/day in the period 21–28 days after stocking (DAS) and the highest SGR of 21% in the period 7–14 DAS. Patin fish also showed good growth performance (DWG = 1.29 g/day; SGR = 12%), while gourami and catfish showed slower growth with DWG ranging from 0.29–0.86 g/day. Water spinach plants achieved the highest CGR of 2.14 g/day in the period 14–21 days after planting (DAP), indicating optimal vegetative growth phase.