where DWXt0 and DWXt24 refer to N or TP concentrations in water
samples obtained just prior to feeding and 24 h later, respectively,
in a tank with closed valves, and L=volume of the tank in liter. Excretion
of TAN was derived similarly to DWX.
The feed conversion ratio (FCR, g g−1) was calculated based
on the biomass weight gain and the registered feed intake (feed
administered−feed waste) as (Guillaume, 2001):