When aquaculture is carried out in a pond, the closed nature of the pond itself is likely to cause water flow problems and water quality problems. In addition, the degree of industrialization is constantly deepening and the speed of urbanization is accelerating. This has increased environmental pollution to a certain extent More water quality issues.
1. The importance of pollution control in pond aquaculture
1. Water pollution will affect the aquaculture itself
In the process of breeding aquatic products, the standard of water quality is very high. If the water quality is good, the quality of the aquatic products produced will also be very high. If the water quality is poor, or some indicators exceed the range that the aquatic product itself can bear, then it is very likely to affect the normal growth of the aquatic product, and even lead to the death of the aquatic product, resulting in huge economic losses.
2. Water pollution will reduce the quality of aquatic products and endanger human health
Aquatic products raised in ponds with poor water quality are also of low quality, which not only taste unpalatable, but also cause harm to people's bodies. With the continuous development of modern society, people's quality of life is also rising, but the natural environment The quality is gradually decreasing. Water quality problems will directly affect the normal growth of aquatic products, and will also cause indirect harm to the human body. Therefore, people pay more and more attention to the healthy breeding of aquatic products. In addition, solving the water quality problem is an important basis for the aquaculture industry to achieve high-quality production. It can provide a healthy and ecological development environment for the aquaculture industry, and can also effectively promote the continuous progress of the pond aquaculture industry.
2. Common problems and solutions
1. Problems and solutions of pH
Aquaculture must control the pH value of water. Only a pH value between 6.5 and 8.5 is suitable for aquaculture. However, due to the difference between regions and the corresponding oxidative decomposition reaction of chemical substances in the water body, it will cause the water body The pH value changes. If the pH value is low and the water body is acidic, it will directly reduce the oxygen carrying capacity of the fish itself, leading to hypoxia, which will cause the "floating head" phenomenon in the breeding. The reduction in oxygen consumption slows down the fish's metabolism, and the fish itself becomes hungry but cannot eat. If the pH value is too high, the water body is strongly alkaline, such water body will be more terrible, it will corrode the gills of fish, and to a great extent, will also cause a large number of fish to die. In addition, changes in pH will also change the composition of ammonia and hydrogen sulfide in water, these factors will directly affect the normal growth of fish.
If the pH value in the water body is low, people can splash appropriate amount of quick lime in the water. It should be noted that the amount of quick lime needs to be grasped. At the same time, it is also necessary to regularly check the water quality and determine the amount of quicklime added according to the test results. When the pH value is moderate, some quick lime can also be sprinkled in an appropriate amount, which not only plays a disinfecting role, but also maintains a stable pH value. If the pH value in the water body is too high, an appropriate amount of bleach powder can be spilled. Spilling method is the same as quick lime. In addition, new water needs to be added regularly, which can also adjust the pH.
2. Dissolved oxygen changes and solutions
The dissolved oxygen (DO) content in the water will also directly affect the normal growth of fish. The problem of oxygen supply in the summer is critical. Because the temperature in summer is relatively high, it will lead to the solution to the common water quality problems of pond aquaculture, which will cause the dissolved oxygen in the water to decrease. At the same time, the high temperature will promote the growth of algae and aerobic bacteria in the water. Their excessively rapid growth will cause Dissolved oxygen in the water drops excessively, and as a result, fish will not like to eat. In severe cases, large-scale death will occur. In winter, although the temperature is low, but the density of overwintering is large, we should also pay attention to the oxygen supply of the pond water body.
It is easier to solve the problems caused by DO. It is very important to clean the bottom of the tank regularly. The sludge contains a large number of aerobic bacteria, and their growth will reduce the DO in the water. Secondly, attention should be paid to the stocking density, and scientific and reasonable stocking density can harvest better returns; scientific feeding , Can not only reduce the waste of bait, but also prevent the deposition of bait, produce organic matter to promote the growth of microorganisms and consume oxygen; pay attention to the cultivation of green plants in the water body to improve the DO in the water body; the water body should be regularly tested and the water body improver should be added So that the water body can realize self-regulation to a certain extent.
3. The influence and solution of nitrite
Nitrite is an intermediate product of the conversion of ammonia to nitrate. Under normal circumstances, other microorganisms such as nitrifying bacteria will convert it into nitrate, which does not affect the growth of fish. However, in some cases, such as using a disinfectant at the wrong time to kill the nitrifying bacteria responsible for nitrification, nitrite will be enriched. The enrichment of nitrite is also related to others. For example, the decomposition of sludge at the bottom of the pond, excess bait, fish excrement, etc. will produce nitrite. The increase of nitrite content will cause the normal hemoglobin in fish blood to decrease, thus reducing the blood's oxygen carrying capacity, causing its own metabolism to slow down, thus affecting growth.
Common solutions are: timely desilting, which can effectively prevent the silt at the bottom of the tank from being too thick, too many microorganisms participate in oxygen consumption activities; scientifically and rationally feeding, can reduce the waste of bait and excessive bait to promote the growth of microorganisms; Introducing new water; cultivating nitrifying bacteria and promoting their growth to prevent the accumulation of nitrite; increasing aeration equipment and increasing the DO in the water body are also effective measures to prevent excessive nitrite.
4. Impact of cyanobacteria and solutions
Cyanobacteria is a problem often encountered in aquaculture, and the occurrence of cyanobacteria has caused serious impacts on aquaculture. Its excessive reproduction will cause the reduction of dissolved oxygen in the water, and a series of complications caused are not conducive to the healthy growth of fish.
Before solving the problem of cyanobacteria, there should be a systematic understanding and understanding of the growth and reproduction characteristics of cyanobacteria. The growth cycle of cyanobacteria is about one month. The first ten days are the growth period of cyanobacteria. At this time, the cyanobacteria are not easy to detect, and the transparency of the water body in sunlight is slightly reduced. At this time, it is necessary to control the amount of bait, and add biological agents to improve the water body. In the next ten days, cyanobacteria grew into a peak period, the surface of the water body was quickly covered, and the oxygen in the air was difficult to enter the water body. At this time, it is necessary to salvage the cyanobacteria and add aeration equipment to aerate the water body; the last ten days of cyanobacterial growth enters the decay period, but improper treatment will cause the secondary growth of cyanobacteria. At this time, it is necessary to continue to add aeration equipment for aeration, additionally introduce new water, and add biological agents to improve the water body in time.
In the aquaculture process, problems will occur if the water quality is not properly controlled. The water quality problems directly affect the economic benefits of the aquaculture and the surrounding environment. Therefore, we must treat the prevention and control of water quality correctly during the aquaculture process. The reasons for the formation are to solve these problems through scientific means and effective methods, and to control water pollution, so that the health of the water body can be maintained, thereby providing a good living environment for farmed animals and achieving the goal of green farming.