author(s)
Germán Castro Mejía, Castro Mejía Jorge, Arnulfo Misael Hernández Martínez, Andrés Elías Castro Castellón, Axel Omar Rivera Ramírez and Ana Fernanda González Flores

abstract
This study evaluated the effect obtained on feed efficiency in five treatments with Nile tilapia (Oreochromis niloticus) using a Biofloc system at different densities. The specimens were placed in five containers with 250 L of water each (50, 75, 100, 125, and 150 respectively), and every 15 days 30 organisms were taken, weighed, and measured. At the end of the experiment, the length and weight gain of the fish were evaluated, and the AGR, IGR, KM, FCR, and FCE were obtained. A one-factor analysis of variance was applied to the data obtained to find significant differences (p<0.05) between treatments, and the Tukey technique was applied. The organisms that obtained the highest weight were those grown in the 50 org 250 L^-1 treatment, reaching 677.43±0.33 g in only 98 days of experimentation. The highest TCA of weight and length were presented in the 50 org 250 L^-1 treatment (4.70 g day^-1 and 0.43 cm day^-1 respectively). In general, we can conclude that fish grew better and length at lower rather than higher stocking densities. However, this does not exclude the possibility of higher stocking densities, especially if good water quality is maintained to obtain a better final production.