The objective of the present research was to evaluate phosphorus in diet for pacu (Piaractus mesopotamicus) juveniles on water quality, livestock performance, body yield and carcass chemical composition. A total of 100 juveniles, 25.9±1.32 g average weight were randomly assigned into 20 fiberglass tanks, with five treatments and four replications. The fish were fed four times a day (8 and 11 a.m.; 2 and 5 p.m.), with extruded diets containing 0.40; 0.55; 0.70; 0.85 and 1.0 % total phosphorus. No differences were observed in water quality parameters, except for the concentration of orthophosphate in water, which presented linear increase. The parameters livestock performance, body yield and carcass chemical composition showed no differences for the levels of supplementation of phosphorus in diet. The use of 0.40% total phosphorus meets the requirements of phosphorus for pacu (Piaractus mesopotamicus) juveniles, in addition to releasing lower concentration of orthophosphate in water.
essential mineral; native fish; nutritional requirement; water quality
