Introduction: The breeding density in this area is high and the water source pollution is serious. During the high-temperature period of pond breeding, aquatic plants will rot, the water will be red and the water will be black, and cyanobacteria will explode. In severe cases, "flooding ponds" will occur. Why is it that the water test is always good, but the aquatic plants still have black roots and rotten roots? Why was it that the water was clear and the grass was good a few days ago, but suddenly the water turned dark and the casualties of shrimps and crabs were high? In fact, in addition to the two conventional pollution indicators of ammonia nitrogen and nitrite, water bodies also have key indicators such as water temperature, air pressure, dissolved oxygen, and saturation. Changes in these indicators will affect the vitality of aquatic plants and the growth of shrimps and crabs. . In recent years, the size and production of shrimp and crabs in this region have generally been lower than before. The most critical reason is the low "dissolved oxygen" in the ponds!

"Dissolved oxygen" in water bodies is as important to shrimps and crabs as air is to humans. It is the guarantee for biological growth, a bridge for material circulation, and the cornerstone of ecological balance.

1. The harm of insufficient dissolved oxygen

1. Low dissolved oxygen will cause shrimps and crabs to eat less food, have poor vitality, and have less nutrient accumulation. Of course, the doubling of molting shells will be small;

2. Low dissolved oxygen will accelerate the death of shrimps and crabs with poor physical fitness. This is why the casualties of shrimps and crabs increase when the weather is hot;

3. Low dissolved oxygen, It will cause the organic matter in the pond to be incompletely decomposed and produce many harmful substances, such as ammonia nitrogen, nitrite, etc., which will affect the constitution of shrimps and crabs;

4. Low dissolved oxygen will also cause bottom odor and bad bottom. The aquatic plants will also rot and rot, thus polluting the water quality;

5. Low dissolved oxygen will breed many anaerobic pathogenic bacteria, increasing the risk of shrimps and crabs suffering from enteritis, carapace ulcers, and ascites. and other bacterial diseases;

? ? Diligent changes to prevent hypoxia?

Key indicators of water bodies: dissolved oxygen, water temperature

2. How to judge hypoxia? Oxygen to prevent hypoxia?

1. Experience and observation

2. Scientific testing

All-weather testing equipment (Haikong Online)

June 8, On the 9th, the weather turned from cloudy to light rain, and the dissolved oxygen in the pond changed. It can be seen that the time period when the dissolved oxygen in the pond is lowest is from 2 a.m. to 10 a.m.

On June 10, it became cloudy and sunny. It can be seen that the lowest time period of dissolved oxygen is from 3 to 7 am.

On June 20, it was a cloudy and rainy day, with cooling and rainfall, and the dissolved oxygen changes of the aerator were turned on throughout the day.

In-store water testing (Hach dissolved oxygen meter)

3. Misunderstandings about specifications and hypoxia.

Misconception 1: Shrimps and crabs are not hypoxic before they land on the grass

Truth: From the above analysis, we can know that hypoxia is a process, and by the time the shrimps and crabs land, they are already very In serious cases, the losses caused at that time will be difficult to make up for. Therefore, when there is slight hypoxia in the water body, we must deal with it according to the actual situation to avoid making the hypoxia situation continue to worsen!

Myth 2: Drugs that increase oxygen have a short effect and are not effective

The truth: There are often a few days in a year that cause severe hypoxia due to the influence of weather or drugs. A lack of oxygen will continue to affect the feeding and molting of shrimps and crabs, and the consequences will be serious. Therefore, we only have to pay more attention to improving the bottom, increasing oxygen, pumping more water, and paying attention to water adjustment. We must be aware of prevention in advance during hypoxic days, so as to reduce losses. When severe hypoxia occurs, you cannot ignore it. While increasing oxygen, you also need to pay attention to the recovery of the shrimp and crab's physique, proper detoxification and nutritional supplements, which will have better results!

Misconception 3: Shrimps and crabs will not eat food if the pH value is high

Truth: Recently, when our pharmacy technician tested the water, he found that the pH value of many ponds was high, which caused a lot of crab breeding. Is the chef worried about not eating the ingredients? Will it hurt the shrimps and crabs? We think this is too much to worry about! On the contrary, a high pH value is a sign of good aquatic plants. Ponds with a lower pH value (in the first two years) have more organic matter (such as muddy water, thick water, black and red water) and oxygen consumption. In large ponds, it is easy to suffer from hypoxia, and the size of shrimps and crabs will not be too large.

Another point, don’t use lime to increase the pH value of ponds with low pH values. Increasing the pH value is not the key, but increasing the dissolved oxygen in the water body is the key!

Crabs in ponds with good dissolved oxygen will thrive

Finally, please remember Liyang’s eighteen-character motto:

Controllable weight, add more oxygen, and change the bottom diligently

Skillful water stabilization, regular health care, less insecticide

Tips: When purchasing "Bishuian (enhanced type)", please look for the Liyang trademark

Liyang Aquatic Products Pharmacy Luoshan Store

Telephone:

Xu Xianxiang 15171185357

Lu Chao 15327782787

Liu Xiang 15308613437