Bacteria production using fish waste as substrate was
enhanced by organic carbon supplementation. The resulting
VSS concentrations in the reactor were clearly dependent on
the concentration of carbon supplement. Measured and
calculated yields were at the lower range, compared to values
found in literature. During the experiments, bioenergetic and
kinetic parameters were determined, such as the metabolic
maintenance costs (0.08Cmol/Cmol h) and the maximum
growth rate (0.2–0.5h1). Based on the yields, nutrient
conversion and growth rate, it is recommended to apply a
HRT of 5–9 h. This resulted in a calculated reactor volume of
28–51 l/kg feed. If bacteria biomass were harvested, a maximum
of about 100 g of bacterial protein/kg feed would be
produced. In addition, the overall conversion of inorganic N
waste was on average 90% and of the ortho-phosphate about
80%. Producing bacteria using the drumfilter effluent as a
source of nutrients may, therefore, produce additional protein
and lower the overall nutrient discharge from recirculation
aquaculture and increase system’s sustainability, provided
that bacteria biomass is harvested.