ABSTRACT This study evaluated the potential for rearing matrinxã (Brycon amazonicus) with different crude protein (CP) levels and using production performance, water quality, and animal welfare as indicators. To achieve this, 720 juvenile fish (3.65±0.17 g) were distributed in 24 experimental units (200 L). The study, which lasted for 60 days, followed a factorial design (2 × 4) with two production systems: biofloc technology (BFT) and clear water (CW) and four CP levels (24, 30, 36, and 42%) in the […]