Given the crucial roles of sulfur amino acids methionine and taurine in aquatic animals, especially in marine fish, two parallel trials were conducted to evaluate varying dietary levels of these amino acids on growth performance of juvenile red snapper (Lutjanus campechanus) in clear water recirculating systems. Both trials utilized iso-nitrogenous 36 g 100 g-1 and iso-lipidic 10 g 100 g-1 diets. In Trial 1, five diets contained supplemented taurine levels ranging from 0.00-0.80 g 100 g-1, resulting in total dietary levels of 0.17-0.95 g 100 g-1, with fish having initial weight of 10.16 ± 0.05 g. In Trial 2, ten diets were formulated with fish having initial weight of 15.44 ± 0.08 g. Eight diets contained added methionine ranging from 0.020-0.220 g 100 g-1 with 1.13 % taurine, while two additional control diets contained no added methionine with 0.15 % and 0.64 % of taurine, respectively to assess taurine-methionine interactions. This resulted in total dietary methionine levels of 0.57-0.79 % across all ten diets. Preliminary results demonstrated contrasting responses between trials. Trial 1 showed significant treatment effects (P < 0.001) on all growth parameters except survival, with fish fed 0.17 g 100 g-1 taurine exhibiting reduced performance with 43.47 g average weight and feed conversion ratio of 1.81 compared to improved growth achieved at ≥0.27 g 100 g-1 with 56.63-60.29 g average weights and feed conversion ratio of 1.35-1.38. Conversely, Trial 2 showed no significant differences among diet groups (P > 0.05), with average weights ranging from 50.15-55.44 g and feed conversion ratio of 1.26-1.40. These findings indicate that taurine appears to be the first limiting sulfur amino acid in red snapper diets, requiring at least 0.27 g 100 g-1 for enhanced growth performance. Methionine requirements may be lower than 0.57 %, as supplementation above basal levels provided no growth benefits when adequate taurine was present. Ongoing plasma amino acid profile analysis may provide additional insights into sulfur amino acid metabolism and utilization in juvenile red snapper.