Ahmad Alfito Gymnastiar, Ating Yuniarti, Seto Sugianto Prabowo Rahardjo, Yunita Maimunah, Rani Yuwanita, I Made Dedi Mahariawan, Yuni Widyawati, Moh Sholichin, Anik Martinah Hariati
The nitrogen cycle is crucial in aquaculture, particularly biofloc technology (BFT), where microbial communities regulate nitrogen dynamics to maintain water quality. This study evaluates the impact of Pure Nano Oxygen Bubbles (BFT-PNOBs) on nitrogen cycling and its subsequent effects on the water quality, feed efficiency, and growth performance of Nile tilapia (Oreochromis niloticus) compared to conventional BFT. Over 56 days, the total nitrogen concentration in both systems was 118.54–119.49 mg/L. NH4+ concentrations were consistently lower in BFT-PNOBs at 0.63 mg/L than in BFT at 0.70 mg/L, suggesting a more efficient nitrification process facilitated by higher dissolved oxygen (DO) levels of 7.72 mg/L in BFT-PNOBs compared to BFT (6.67 mg/L). The selectivity of nitrogen transformation into bioavailable forms was also more efficient in BFT-PNOBs, with 58.47 % of nitrogen converted into microbial biomass and gaseous nitrogen, compared to 38.78 % in BFT. Additionally, with carbon maintained at ∼250 mg/L in both systems, the higher and more stable C/N ratio observed in BFT-PNOBs and BFT (13.99 and 10.14, respectively) reflects more efficient nitrogen removal and microbial assimilation. The superior nitrogen management in BFT-PNOBs minimized toxic nitrogen accumulation, stabilized water quality, and enhanced fish performance, resulting in a higher final body weight of 57.13 g compared to 48.08 g in BFT and a greater survival rate. These findings suggest that nano-oxygen bubble-enhanced biofloc systems optimize nitrogen cycling, supporting sustainable aquaculture by reducing environmental nitrogen waste, enhancing fish growth, and improving feed utilization. © 2025 Elsevier Ltd
Master's Degree Program in Aquaculture, Faculty of Fisheries and Marine Science, Brawijaya University, Jl. Veteran, East Java, Malang, 65145, Indonesia; Department of Aquaculture, Faculty of Fisheries and Marine Science, Brawijaya University, Jl. Veteran, East Java, Malang, 65145, Indonesia; Water Resources Engineering Department, Faculty of Engineering, Brawijaya University, Jl. Veteran, East Java, Malang, 65145, Indonesia; Aquatic Biofloc Research Group, Brawijaya University, East Java, Indonesia; Center for Shrimp Research Commodity, Brawijaya University, East Java, Indonesia