Nitrogen cycle in circulating aquaculture system

First of all, in a relatively fixed density of aquaculture water, in addition to the necessary water evaporation, other material will not disappear without reason or produce. Variable mainly come from the fish food into the water and sewage discharged all sorts of waste. Of course, into the fish eat will be greater than the amount of waste discharge. And the balance part is the organism's own consumption, part become the body of an organism -- they will be from small to big fish. This is the final circulating water aquaculture. We pursue this eventually produce the amount of fish, not only will the speed of the attention they produce. In my company's customers, part of the circulating water aquaculture South America white shrimp farms, even the four seasons in a year out of the three quarter into a shrimp. Considerable economic benefit.

When nitrogen exist in the fish feed, it is generally composed of protein in the form of. After feeding, most will be eaten by fish, a small number of feed will not eat scattered in aquaculture water. Under the action of decomposing bacteria, they gradually transformed into amino acids, further into ammonia. Part of being eaten by the fish after a fish digestion, is converted to ammonia. All roads lead to Rome ammonia, it is a substance soluble in water. It will produce after hydrolysis ammonia ions and hydroxyl ions. But this chemical reaction is a reversible reaction. When the hydroxyl ions concentration in the water is higher, reaction to the left, ammonia concentration will be increased. Vice versa. Under the action of nitrifying bacteria, ammonia will be converted to nitrite. Nitrite is a volatile substance. In the case of high REDOX potential, will be oxidized into nitrates. At this time if there is a denitrifying bacteria, nitrates are denitrifying nitrogen. In this way, water adding nitrogen element completes a complete transformation process.