Impact of Diverse Fertilization Practices and Supplementary Feeding Regimes on Water Quality, Plankton Abundance, Growth, Survival, Blood Parameters, and Economic Returns of Grey Mullet (Mugil cephalus) in Nursery Ponds

The grey mullet (Mugil cephalus) is a significant aquaculture species known for its rapid growth, versatility, and high market demand. However, nursery-stage mortality, slow development, and high production costs continue to limit its profitability, particularly in earthen pond systems. One of the most significant issues is a lack of standardized and cost-effective feeding and fertilization systems that may optimize natural food production, maintain appropriate water quality, and improve fry survival and growth. The current study examines how various fertilizers and feeding techniques affect the water quality, plankton quantity, growth performance, survival rate, certain blood parameters, and economic assessment of raising grey mullet (Mugil cephalus) fries in eastern ponds. For seven months, grey mullet fries weighing 0.35±0.02 g were planted in nine earthen ponds (1000 m2 each) at a pace of 50,000 seeds. Three treatments were studied in triplicate: organic fertilizer with aquafood (T1), inorganic fertilizer with aquafood (T2), and aquafood only (T3). The measured water parameters were determined to be within an optimal range during the study period, with significant (P