Brycon moorei is known to be an opportunistic omnivorous species. It is not known about their nutritional requirements and zootechnical responses concerning formulated diets at any stage of development in this species. In a recirculating aquaculture system (RAS) and with a completely randomized quintuplicate design, an ad libitum feeding protocol was applied, which included forage larvae of Prochilodus magdalenae, Artemia salina, and balanced feed with inclusion levels from 35% to 55%. of crude protein (CP). For this, larvae 22 hours after hatching (HPE), with an average initial weight and length of 3.07±0.69 mg and 6.069±0.22 mm, respectively, were seeded at a density of 17 larvae L-1 in tanks with an effective volume of 60 L. The main zootechnical parameters were analyzed about the experimental diets (Weight gain (WG-mg); daily weight gain (DWG-mg); length gain (LG-mm). Daily gain in length (DGL-mm), feed conversion (FC), consumption (C, mg/day/larva), specific growth rate (SGR), condition factor (K) and survival (S%)). The results of the zootechnical parameters indicate that the best diet was significantly 45% CP when compared to the other CP levels used (Table 1). In the mean comparison tests between weight gain (GP) and % CP, the polynomial regression model determines that the probable protein requirement for this stage corresponds to 48.5% CP (Figure 1).