For the test of formation and maintenance of microbial aggregates generated in the post-larvae culture super-intensive system, a significant difference was observed (p b 0.05) in the microbiological count of the water on the seventh day of testing, when the total count of Vibrio spp. in water was lower in the groups treated with Bacillus spp. (1 × 104 CFU•mL−1) than in the control group.