Table 1.

Requirements of rainbow trout in closed farming systems [34,36,56,209,222,223].

Requirements	Values
Dissolved oxygen (DO)	>5.0–5.5 ppm
Water quality	Good flow, clean freshwater
pH	6.7–8.2
Growth rate	Rapid
Marketable size	350 gr up to one kilo in less than a year
Protein content	High (50%)
Circular tank containing	300 gallons of water
Density	7.26–20 kg/m3
Temperature	9–21 °C
Nitrates	<75 mg/L