Aquacultural water quality problems revealed

With the continuous improvement of aquaculture technology, high-density, multi-species farming mode has been widely adopted by the majority of farmers, but in such a farming environment, the use of inputs are also increasing, which is easy to cause the deterioration of water quality, the decrease of dissolved oxygen content, the increase of harmful substances content, directly leading to pond pond and disease outbreaks, the light will affect the feeding and growth of pond fish, and the heavy will cause fish death.

 

Signs and causes of deterioration of fish pond water quality

 

The deterioration of pond water mostly occurs in high temperature season or rainy season, due to the fermentation decomposition of humus and the excessive reproduction of aquatic plants.

1. The water color is dark brown with turbidity

The water color is dark brown with turbidity is caused by too much humus in the pool and too fast decomposition of corruption. This water is often acidic, which is not conducive to the reproduction of natural food and the growth of fish.

 

2. Brown-red or oil-green droplets or particles appear on the water surface

The appearance of brown-red or oil-green droplets or particles on the water surface is generally caused by the proliferation of blue-green algae, and most of the blue-green algae can not be used as bait by fish, but consume nutrients, drag down the water quality, inhibit the reproduction of digestible algae, affecting the growth of fish.

 

3. There is a floating film on the water surface

The water surface has a floating film (commonly known as "oil skin"), which is the fat body after the death and corruption of organisms in the water body, and is formed after adhering to dust or dirt.

More gray black, fish swallowed, not conducive to digestion; At the same time, the surface of the floating film also affects the oxygen dissolution in the water.

4, the water surface often bubbles floating water color gradient pool water with astringent smell

There are often bubbles on the water surface, the water color gradually changes, and the pool water is astringent with fishy odor, which is caused by carbonic acid, hydrogen sulfide, ammonia nitrogen and biogas produced during the decomposition of humus. These gases are toxic and have certain harm to aquaculture animals.

5. Fish activity is abnormal

The activity of fish is abnormal, sometimes rotating on the surface of the water, and not sinking for a long time (some fish diseases also have this phenomenon); Sometimes after floating head up, slow to sink, or gradually reduce the amount of food.

Pond water is not only the breeding place of fish, shrimp and crabs, but also the breeding place of natural food. The quality of water quality is closely related to their healthy growth and high yield.

 

From the color of the water can judge the quality of the water quality, the following three kinds of water quality, can be considered to be better.

1, mung bean color: the main types of phytoplankton are green globular algae and crypto-algae, diatoms, and sometimes yellow-green algae, etc., with transparency of about 25 to 30 centimeters.

2, light brown with green: high transparency, the main types of phytoplankton are diatoms, chlorella, chrysochlorella and yellow green algae.

3, oil green: the main species of phytoplankton are cryptomyces, diatoms, part of chrysococcus and part of Chlorella. When crypto algae and chlorella are abundant, transparency is lower.

When the weather is hot, there is no bubble or film of any color on the water surface.