How to deal with high ammonia nitrogen in industrial aquaculture water bodies?

When engaging in aquaculture, excessive ammonia nitrogen can bring a series of problems, among which * the main one is that it leads to a decrease in the immunity and resistance of farmed fish and shrimp, reduced feeding, slow growth, and increased susceptibility to various diseases. In order to gain a deeper understanding of this issue, this article will explore in detail the production of ammonia nitrogen in aquaculture, its harm to aquatic organisms, and how to effectively prevent and control ammonia nitrogen in industrial circular aquaculture.

Firstly, it is necessary to understand the source of ammonia nitrogen. The excrement (feces) and bottom organic matter of fish and shrimp will produce ammonia after ammonification. When the density of fish and shrimp in the aquaculture pool increases, the concentration of ammonia will also increase, and the impact on fish and shrimp will be greater. The toxicity of ammonia to fish and shrimp actually depends on the amount of ammonia in their bodies.

So, where does the ammonia nitrogen in aquaculture water come from? Firstly, the nitrogen-containing metabolites of aquatic animals such as fish, shrimp, and crabs are mainly excreted from the gills in the form of ammonia. The feces of fish and shrimp, feed that has not been eaten, and dead algae and other organic matter will be decomposed by heterotrophic bacteria, and their metabolic product is ammonia. When the feed consumed by fish and shrimp decomposes in the body, a portion of the feed protein will serve as energy to produce ammonia, which is excreted through respiration. In addition, when the water lacks oxygen, various organic matter, nitrate, and nitrite will undergo denitrification under the action of anaerobic bacteria, which will also lead to the accumulation of ammonia nitrogen.

The harm of ammonia nitrogen to aquatic animals should not be underestimated. Chronic ammonia nitrogen poisoning can lead to reduced feeding, slow growth, incomplete molting, tissue damage, and reduced oxygen transport between tissues in fish and shrimp. Acute ammonia nitrogen poisoning can cause aquatic organisms to experience excitement, loss of balance, convulsions, and even death. Even if the concentration of ammonia nitrogen is not sufficient to cause death, it will seriously affect the growth rate and disease resistance of fish and shrimp, thereby reducing the effectiveness of aquaculture.

In traditional aquaculture, methods such as changing water, adjusting pH, planting aquatic plants, constructing nitrification systems, reducing feeding rates, aeration, algae cultivation and water regulation, and using drug degradation are commonly used to control ammonia nitrogen. However, these methods often only reduce ammonia nitrogen concentration in the short term and cannot fundamentally solve the problem.

In contrast, industrialized circular aquaculture has more obvious advantages in controlling ammonia nitrogen. In this aquaculture model, the pool water needs to be recycled, and the water continuously flows and is purified. Through biological treatment technology, nitrifying bacteria can be cultivated to directly decompose ammonia nitrogen. At the same time, specialized aquaculture water treatment equipment can remove impurities such as proteins, dissolved enzymes, solid suspended solids, iron and manganese ions, while ultraviolet radiation can kill bacteria and viruses in the water. This series of measures can effectively control and remove ammonia nitrogen, improve water quality, and thus ensure the healthy growth of fish and shrimp.

Overall, in order to effectively control ammonia nitrogen in aquaculture, it is not only necessary to understand the sources and hazards of ammonia nitrogen, but also to choose appropriate control measures based on the actual situation. The industrial recycling aquaculture model undoubtedly provides us with a more efficient and sustainable solution.