Use of a zero-exchange brackish water biofloc system to increase growth, survival, and color intensity of guppy, Poecilia reticulata (Peters 1859)

C:N ratio Rice bran Water quality Ornamental fish Growth


August 25, 2023


Biofloc technology is based on carbon metabolism and nitrogen immobilizing microbial activities. The present study aimed to maintain water quality and increase the production performance of guppy Poecilia reticulata (Peters 1859) in a zero-water exchange brackish water biofloc system. Twenty P. reticulata were stocked into each treatment and control tank in triplicate and fed a formulated diet at a rate of 3% of body mass daily. In control-1, 50% water was exchanged weekly following the industrial practice, and no water was exchanged in control-2 and the treatment. Depending on the concentration of total ammonia nitrogen (TAN) in water, rice bran as a carbon source was added to the treatment tanks to keep the C:N ratio at 20:1. Water quality in biofloc treatment and control-1 was within the favorable range for P. reticulata. TAN and pH in tanks with zero water exchange were significantly higher (P<0.05).  Weight gain, specific growth rate, survival rate, final weight and length of P. reticulata in the biofloc treatment were significantly higher (P<0.05) than controls.  Fish reared in the biofloc treatment had an intense bright red body and fin color compared to those in the controls. Biofloc technology can be adopted to maintain water quality and enhance the production performance of P. reticulata in zero-water exchange brackish water culture systems.