oreochromis niloticus is a tropical fish with a suitable temperature range of 16-38°C, an optimum growth water temperature of 24-32°C, and the fastest growth at 30°C. The upper limit of lethal temperature is 42°C and the lower limit is 10°C. 14-15 ℃ loss of appetite. 10°C does not eat at all.

Oreochromis niloticus has strong hypoxia resistance. When the water temperature is 22-25, the dissolved oxygen content is 0.7 mg/L, showing only a weak floating head, but it can still eat; when the dissolved oxygen content is 2.24 mg/L, the food intake is vigorous. In order to maintain normal growth, the dissolved oxygen in the water must be kept above 3 mg/L and below 0.1 mg/L asphyxiation. Ammonia nitrogen below 1 mg/L. The pH value is between 7.5-8.5. Carbon dioxide is below 50 mg/L.
Oreochromis niloticus is a hygrosaline fish that can adapt to changes in a wide range of salinity and can be directly moved from fresh water to a salinity of 15‰. in seawater, and vice versa. If it starts from a low salinity (below 15‰), gradually increases the salinity, and after short-term domestication, it can grow normally in seawater with a salinity of 30‰, and can still survive in a salinity of 40‰.
Oreochromis niloticus generally lives in the bottom of the water, and swims to the middle and upper layers in the morning with the change of water temperature, swims close to the surface layer at noon, moves in the middle and lower layers in the evening, and stays at the bottom of the water at night and dawn. Or when pulling the net, jump first and then dive into the muddy bottom of the water, exposing its mouth out of the mud and not moving.
In the juvenile stage, it feeds almost exclusively on zooplankton - rotifer eggs, copepods, nauplii and small cladocerans, and gradually becomes omnivorous as the individual grows. The type of food in the natural water body depends entirely on the type and quantity of natural food in the water body, usually phytoplankton and zooplankton, but also ingesting benthic organisms, aquatic insects and their larvae, and even small fish, shrimp, and sometimes Also eat aquatic plants. Adult fish mainly feed on phytoplankton, of which cyanobacteria account for 70%. Some algae that are difficult to digest and utilize by fish such as silver carp and bighead carp can be digested and utilized well by the fish. The assimilation efficiency of oreochromis niloticus was 75% for Colleum, 70% for Microcystis, 75% for Anabaena, 79% for Rhizobium and 49% for Chlorella. Under the condition of artificial feeding, in addition to the above natural bait, they also ingest various commercial feeds, such as bran, oilseed meal, bean dregs, distiller's grains, and artificially compounded bait. Raising the fish with various commercial feeds can achieve remarkable results. In the production, the method of combining bait and fertilization can also be adopted, which can achieve better economic benefits.