<h2>【Big coffee on shrimp】Breaking the routine, can good algae really raise good shrimp? </h2>
2016-10-23Prawn farmer shrimp farmer
Good algae? Good shrimp?
We often read articles that teach you to determine which algae is good or which water color is suitable for shrimp farming. However, as a farmer, I found that this principle is not the truth. Sometimes the algae are good, but the shrimp have fallen; and the water color of the old Wang family next door is very poor, and there is not even algae in the pond, but the shrimp is well raised. What can I do if this happens? Don't worry, and see how the big coffee analyzes!
Is there really an algal phase that is absolutely suitable for shrimp growth?
@ a cow Tian Yang: It is better to mix green algae and diatoms, like the tea brown color based on diatoms, it is difficult to recover after the occurrence of inverted algae. Diatoms are unstable, and green algae are relatively stable.
@Cumulonimbus at sea: not necessarily. There are also beneficial algae (spirulina) in cyanobacteria, and there are also algae that are not suitable for fish and shrimp in the green algae diatoms (tetracytos, sponges, water mesh algae; boat-shaped algae, box-shaped algae, etc.) After all, there are too many species of algae. There are good and bad, you can't just say which is good and which is bad! Now many masters are adapting shrimp to algae phases, rather than diverting water to adapt to fish and shrimp.
@Shrimp Soldier Shrimp Sauce: What algae is good? It should depend on whether you are from a nutritional point of view or a water stability point of view. My personal opinion, if you consider it from the perspective of cultivating a relatively stable water body, it should be a rich variety of varieties and balance each other, not which kind of algae is good! Why are natural water bodies so stable? Because after years of evolution by nature, the algae varieties in it are rich and balanced, and it is possible to use nitrogen, phosphorus and potassium as soon as possible after entering natural water than suitable organic and inorganic fertilizer water, so that it is easy to be relatively rich, balanced and durable.
@ shrimp guy: The best algae used in shrimp is spirulina, seaweed, algae, bone stripe algae, chlorella, in the breeding process can not use these algae alone, from an algae gate to an algae species, including too wide a range, do not deliberately want what algae gate, shrimp stable adaptation to this type of algae water quality is the most critical.
@ A cow Tian Yang: @ Sea Cumulonimbus Let the shrimp adapt to the algal phase, and the inferior algal phase can also make the shrimp suitable? Can shrimp resist the toxins produced by cyanobacteria after death? Please advise. That requires a high aeration requirement.
@ Sea Cumulonimbus: Now many people encounter a really poor algal phase and directly kill the algae-free turbid water mode. A five-acre earthen pond only needs a gas pump of up to 4,000 yuan plus PVC pipe to withstand the conventional 1,000 jin mu production. That doesn't seem like a lot of demand, does it? Unfortunately, in the breeding pond, spirulina can cause the bottom to deteriorate; the sea chain algae, algae, and bone stripe algae are all red tide organisms, and the harm is needless to say; chlorella can cause ultra-high pH. Alas, I am also surprised that the algae used in basic aquatic products for biological food for seedlings have more or less drawbacks!
@ shrimp guy: the control of the amount, there are advantages and disadvantages, after the large number of algae, bone algae can not be ingested in time, is a disadvantage. After the death of the algae, the bottom is bad. So if you want to pursue perfection, you have to pay a price.
@Cumulonimbus at sea: Indeed. So although we know that algae breeding is very effective, only no more than five shrimp fry companies in the market really dare to use this method. Because the algae will be polluted after eating, and it will also be polluted when it is not finished. As far as I know, algae breeding must be accompanied by live bacteria breeding. As for the proportion of collocation, many manufacturers are still debugging.
@ Shrimp Guy: It is recommended that the majority of farmers do not deliberately pursue what algae water color, shrimp in the pond environment stable growth is our purpose. To put it bluntly, there is no algae that is the best, only better use of the value of algae existence, which requires farmers to carefully explore and experience. Bacteria control algae, algae control water, water control shrimp, biological chain recycling rules.
@Shrimp Soldier Shrimp Paste: The specific kind of algae is good or bad, which is artificially defined. Our aquaculture water environment is also an ecosystem, there is no need to deliberately pursue what kind of "good" algae to cultivate, as long as it is rich, balanced, long-lasting and stable. Anything will be the opposite! Red tide is not a certain kind of algae reproduction excess, and a large number of aerobic, but also inhibits the reproduction of other algae.
"The water is good but the shrimp has poured" What do you think?
@ Xiao Chen: The water is good, the shrimp have poured down, how do you see it!
@ Shrimp Guy: The water is on the middle and bottom of the three layers, which level is good for water? The upper water is good and cannot include the bottom water at the same time, the bottom water includes too many physical and chemical factors, and no one has specially detected the bottom indicators including soil quality in the breeding problem. Shrimp, will not be hung up for no reason.
@ Zhejiang shrimp farmer Amin: Personally believe that the deterioration of water quality is gradual, shrimp have a certain degree of stress resistance, but at the critical point shrimp will appear various symptoms. But if at this time you strongly adjust the water, although the water is good, the shrimp are hanging. Too much based on theorization or focusing only on factories can not save the industry, which is one of the reasons why many experts and multi-sector technicians dare not directly engage in aquaculture or repeatedly encounter obstacles in the industry and are not recognized. Only down-to-earth, multi-party consideration, and multi-party argumentation can take root and blossom.
@Xie Quanzhong Zhongshan Zhongge: Well, there is a good and shrimp "relatively healthy" good based on their own cognition. It is equivalent to "out of chapter". At one point, this phenomenon does exist. Mainly only see the water, do not leave the water to see the other.
@ Twenty sentences, Wantian Soil: I came across a number of small sheds in Xinghua that raise South American white shrimp, that kind of pond with no algae color of water quality eats very well, grows fast, but those ponds with very dark water color, the water color will be unstable, shrimp eat good and bad, the growth is also general.
@Feitian: Good and bad are not absolute, it lies in balance, and it is difficult to succeed in reality by overly idealizing things
One. Cyanobacteria
The occurrence of cyanobacteria depends largely on temperature. Cyanobacteria are sensitive to temperature when they reproduce, and when the water temperature is below 17 ° C, they do not occur in large quantities or do not pose a hazard to fish. When the water temperature rises to 28 ° C, due to the inhibition of the growth of other algae, and at the same time a large number of fish ingestion (high temperature fish feeding metabolism is enhanced), cyanobacteria are prone to form a dominant population and a large number of outbreaks.
(1) pH: Algae like alkaline water, high pH (PH8.0-PH9.5) will promote the occurrence of cyanobacteria, so it should avoid the use of a single method of splashing lime water to improve water quality.
(2) Nitrogen-to-phosphorus ratio: Cyanobacteria can not only use nitrogen in water, but also has a higher ability to utilize phosphorus, low nitrogen-to-phosphorus ratio or high phosphorus-rich water bodies may lead to a large number of cyanobacteria. Appropriately increasing the nitrogen-phosphorus ratio can inhibit the growth of cyanobacteria to a certain extent.
(3) Ecological relationship: Cyanobacteria, together with other algae, constitute the producer of pond ecosystems, providing more than 89% of dissolved oxygen. Therefore, in addition to participating in the material cycle of the ecosystem, these producers also affect the survival of fish.
(4) Causes of cyanobacterial blooms: The key factors of different stages are different, and the formation of cyanobacterial blooms can generally be divided into four stages: dormancy, recovery, biomass increase, and floating. After floating, cyanobacterial blooms are formed, and then the water transfer begins to appear.
(5) The harm of cyanobacteria: Cyanobacteria can change the expansion pressure, in the case of high temperature and strong light weather, gathered in the surface layer of the water body, absorbed most of the sunlight, in their own large number of reproduction while inhibiting the growth of other algae. The large number of cyanobacteria continues to secrete toxic metabolic substances to the water body, which affects the population succession and reproductive cycle of plankton, and can also cause a large number of deaths of some zooplankton.
2. The harm caused by the large number of cyanobacteria
Cyanobacterial particles are difficult to digest by fish and soon become an absolute dominant population after large numbers. This overbreeding, formed through spatial competition for species, will inevitably lead to intraspecific struggles, and the result of this infighting will lead to the death of a large number of cyanobacteria. The mass death of cyanobacteria has led to a sharp decline in the producer of water bodies, resulting in a serious shortage of dissolved oxygen supply in water bodies. At the same time, the death and decomposition of cyanobacteria will also consume a large amount of dissolved oxygen, releasing a large number of toxic substances such as hydroxylamine and hydrogen sulfide. Under severe hypoxia and toxic substance storage conditions, fish, shrimp and crabs will die in large quantities, or even all of them.
2. Naked algae
(1) The occurrence of naked algae produces a water environment in which naked algae blooms: Naked algae like to grow in small water bodies rich in organic matter and static without flowing water, and multiply in large quantities to form blooms when nutrition is sufficient, becoming the dominant species in the water body and quickly occupying the entire water surface.
(2) Suitable temperature and season for bloom formation: The temperature range suitable for naked algae is wide. The suitable temperature for bloom formation is 20-35 °C, and the growth period spans spring, summer and autumn, especially in June, July, August and September.
(3) The harm of naked algae: naked algae is difficult to digest, the utilization rate is low, fish do not like to eat; naked algae is easy to corrupt the water quality when a large number of deaths, and the secreted substances also have a toxic effect on fish, shrimp and crabs.
(4) Prevention and control of naked algae: a large number of water changes, so that the water body forms micro-flowing water. Since naked algae prefer to live in small water bodies rich in organic matter and stationary and without flowing water, a large amount of water change can change this environment, making it difficult for naked algae to multiply in flowing water or new water. It is also possible to use algae killing drugs for local algae killing, and after three days, it is fertilized with fishing fertilizer, which has a good effect.
3. Golden algae, golden algae
(1) Occurrence of golden algae: mainly occurs in ponds with high salinity in coastal saline areas. The water quality of the pathogenic pond is thin, there is no other algae in the water, and the water color is pale yellow.
(2) Symptoms of golden algae poisoning: the surface of the pond is covered with fish, mostly staying at the four corners and the edge of the shallow pool, head to the shore, neatly arranged, stationary under the water surface, not floating, disturbed and unresponsive. Random fishing of dying silver carp and crucian carp can be observed, and it can be found that the base of the body fin is congested and the color of the back of the fish body becomes lighter; the gill cover is opened to find a large amount of mucus in the gills, and the gills are mildly decayed; the fish body is dissected, the intestine is inedible, and there is no obvious lesion.
(3) Prevention and control of golden algae: Inject water with fatter water into the pond or fertilizer water near the pond, and the symptoms of poisoning can be temporarily alleviated. The whole tank is sprinkled with 20g/m3 ammonium sulfate to make the ammonia ions in the water reach 0.06~0.10g/m3 to inhibit or kill the golden algae.
4. Dinoflagellates, naked algae, flying swallow horn dinoflagellates
Dinoflagellates prefer to grow in water bodies with a lot of organic matter, high hardness and slight alkalineity. When they breed in Dali, the water is reddish brown and commonly known as "red water". The harm of dinoflagellates: dinoflagellates is a general term for a large class of flagella, the body is oval, when multiplying, often can change the color of its living waters, some dinoflagellates can be used as bait for some aquatic larvae, but some of them, in the reproductive process, can produce a variety of toxins, causing nerve numbness, metabolic disorders and breathing disorders of fish, and finally lead to death. Odophyllum can also be attached to the fish, live a parasitic life, absorb fish nutrients, stimulate the growth of mucus in the fish body, so that the fish body is like a layer of rice flour, so it is called "powder disease", the prevention and control of dinoflagellates is the same as cyanobacteria.
Fifth, cryptoalgae
Cryptoalgae are one of the most important flagella in natural waters, and ponds rich in cryptoalgae are highly productive. Cryptoalgae has a higher protein content (50% to 70%), and some species, such as Cryptom onas ovata, are also rich in unsaturated fatty acids, especially GLA (octadecatrienoic acid) and EPA (eicosapentaenoic acid) with high nutritional value, which account for 20%, 16% and 4% of the total fatty acid content, respectively. Cryptoalgae have high nutritional value, and their fiber-free cell walls are easily digested and absorbed. As a result, it is one of the high-quality baits for fish and some precious aquaculture animals.
Disadvantages of cryptoalgae: Cryptoalgae have a short growth cycle, are prone to death, and the water color is gray-brown.
Sixth, diatoms: small ring algae, boat-shaped algae, straight-chain algae, feathered algae
The advantages of diatoms are: small individuals and good palatability. The speed and distribution of movement are consistent with the activity habits of the larvae, which is convenient for feeding, that is, there are more opportunities for feeding. Rich in nutrients and easy to digest and absorb, it is non-toxic and its metabolites, and does not affect the normal growth of larvae and seedlings. It is conducive to the reproduction of excellent planktonic single-celled algae, ensuring adequate nutrition of fish and shrimp, ensuring that fish and shrimp fry are full and fast, enhancing disease resistance and improving survival rate. Efficient, no residue, protect the breeding environment, stabilize water quality, do not pollute the pond. Effectively reduce the ammonia nitrogen content in water, high dissolved oxygen, good water color.
7. Green algae: disc star algae, crescent algae, chycoccus algae, hollow algae, hollow star algae, solid bulbous algae, water mesh algae (harmful to fish fry), sponge (water body thin filamentous algae), micromanthus
Advantages and disadvantages of green algae: In our pond culture, most of the chlorella grown in large quantities, because of its small individual size and rich nutrition, it is an excellent erbium feed for rotifers. It can produce a large number of rotifers in the water body, which is more suitable for the cultivation of fish, shrimp and crab seedlings. It can be used directly as an open bait for aquatic seedlings, and can also be used to feed seedlings by breeding rotifers; but due to its small individual size, the utilization rate of farmed finished fish is not high, and it can be used as a water transfer product.
8. Yellow algae, knee-mouth algae
Yellow algae and knee-mouth algae often appear in fertile fish pond water bodies during the warm season. When multiplying, a cloud-like bloom is formed, and the water color is yellow-green. It is a good food for silver carp and bighead carp. Primary productivity is concentrated in temperate or nutrient-rich lakes in winter; in winter, phytoplankton productivity and biomass are generally low in low light, short daylight and low temperatures. When the surface of the water is frozen, if the ice layer is not thick and there is no snow cover, the illumination under the ice is usually much higher than the compensation point of the algae, and photosynthesis can still be carried out to varying degrees. When the ice is made up of thick black ice or long-term snow cover on the ice, net yields turn negative, and biomass is reduced to a minimum due to the easy sinking of non-turbulent algae under the ice.
Article source: Shrimp farmer