Silva, Ellano José daCadete, Ayla Joanna Santos2026-11-112026-11-112026https://repositorio.ifrr.edu.br/handle/123456789/607This study assessed the apparent growth performance of tambaqui and characterized water quality over 238 days in a recirculating aquaculture system integrated with a constructed wetland containing aquatic macrophytes. Forty-two juveniles with an initial mean body weight of 8.91 g were stocked in the system. Fish were sampled during seven biometric assessments, while pH, temperature, dissolved oxygen, total ammonia, and nitrite were monitored intermittently. Mean body weight reached 410.40 ± 130.12 g on day 167 and 427.56 ± 168.08 g on day 238. At the end of the monitoring period, apparent cumulative weight gain was 418.65 g, apparent average daily gain was 1.76 g day⁻¹, and cumulative specific growth rate was 1.63% day⁻¹. The coefficient of variation in body weight decreased from 45.9% at stocking to 24.5% on day 182, then increased to 39.3% at the final assessment. Across the available measurements, pH ranged from 7.37 to 8.00, temperature from 27.7 to 28.9 °C, and dissolved oxygen from 6.0 to 8.0 mg L⁻¹. Total ammonia and nitrite ranged from 0.25 to 3.50 and from 0 to 2.80 mg L⁻¹, respectively. Most of the apparent weight increment occurred during the first 167 days. Because the study comprised a single culture unit without an unplanted control and water-quality monitoring was irregular, the observed patterns cannot be causally attributed to the macrophytes. These findings highlight the need to adjust treatment capacity and oxygenation as fish biomass increases.pt-BRAttribution-NonCommercial-ShareAlike 3.0 BrazilColossoma macropomumBiofiltraçãoWetland construídoAquicultura intensivatcc_graduacaoCIENCIAS AGRARIAS