Two commercial extruded formulated diets for tilapiawere used; fish
were fedwith a 40% crude protein (CP) diet until tilapia reached 65 g and
with a 30% CP diet until the end of the experiment. Daily feeding rate was
restricted to a percentage of biomass in each tank, decreasing with tilapia
growth (4% up to 65 g, 3.5% up to 100 g, 2.7% up to 150 g, 2.2% up to
200 g, 2.0% up to 320 g and 1.8% until the end).