When Tm was low (18 °C) and Ta was high (≥5.3 °C), the reduction in production per batch was not compensated by the higher number of batches, and improving growth rate thus decreased profit(Fig. 4). Consequently, the economic value of TGC (EVTGC)was negative,−0.01 €/kg (Table 7). However, when Ta decreased (less fluctuation), the profit from improving TGC became null or even slightly positive, EVTGC =0.01 when Ta is 4.75 °C. This can be observed also when Tm is 19.5 °C,
when the EVTGC increases with Ta. When Tm was 21 °C, however, the EVTGC started to decrease when Ta was lower than 5.3 °C because the oxygen available at Dlimit started to decrease, constraining the number of fish stocked per batch