The larvae of R. quelen can be cultivated in the biofloc system with a TSS concentration of up to 1000 mg L−1. However, the best growth was registered in tanks with a higher percentage of volatile suspended solids (T200 and T-HET), suggesting that biofloc was also a source of food for larvae. Larval survival was higher in the biofloc treatments than in clear water tanks, which were affected by I. multifiliis. This condition was not found in tanks with bioflocs, which could indicate the probiotic effect of biofloc, or a stress reduction due to higher turbidity.