Copper sulfate, also known as blue vitriol and stone gallstone, is an inorganic compound with the chemical formula CuSO4. It is a transparent dark blue crystal or powder that is soluble in water. The aqueous solution is weakly acidic and appears blue. Copper sulfate is an important raw material for the preparation of other copper-containing compounds. When mixed with milk of lime, Bordeaux liquid can be obtained, which is used as a fungicide for plants and is also used as an electrolyte in electrolytic refining of copper.
Copper sulfate is a heavy metal salt, and its hydrolyzed copper ions (Cu2+) can combine with proteins to form protein salts. The combination of copper ions and proteins will also form complexes (chelates), which will denature and precipitate the proteins. Therefore, it can inactivate the enzymes of parasites and have the effect of killing parasites. It has a strong killing effect on protozoal parasites, and has a strong poisoning effect on protozoa and lower algae with colloids. . Therefore, it is one of the commonly used drugs in the prevention and treatment of fish diseases, and it is very effective. It can treat and kill protozoal parasitic diseases of fish, such as ectoparasitic flagellates, ciliates, straw worms, Chinese worms, etc. It is also lethal to water algae.
Adding copper sulfate to livestock and poultry feed also has a significant synergistic effect. Copper sulfate is an important trace element drug additive required for animal feed. Copper can promote the production of red blood cells in the bone marrow and is one of the important hematopoietic elements. It is related to the formation of red blood cells and hemoglobin, and related to the content of catalase, cytochrome C and cytochrome oxidase in tissues. It also has the function of catalyzing the complexation of iron and promoting the absorption of methionine.
Factors affecting the effect of copper sulfate
The safe concentration range of copper sulfate is very small, and its efficacy is greatly affected by environmental factors. Therefore, it often occurs that phytotoxicity occurs during use or the effect is not obvious after use. The main factors that affect the toxicity and safe concentration of copper sulfate are: pool water temperature, hardness, pH value, organic matter content, etc.
Generally speaking, the higher the water temperature, the greater the toxicity of copper sulfate, and the smaller the safe concentration. In summer, 0.5 g/cubic meter of copper sulfate can be used to kill filariasis, while in winter, 1.4 g/cubic meter of copper sulfate is needed to be effective.
The harder the water, the less toxic copper sulfate is, because carbonate can react with copper sulfate to form a blue-green alkaline carbonate precipitate, thereby reducing the efficacy of copper sulfate.
The pH value is related to the content of carbonate. The more carbonate, the higher the pH value and the less toxic copper sulfate is.
Dissolved organic matter in water, especially proteins and polyhydroxy compounds, can form organic complexes with copper sulfate, thus reducing the toxicity of copper sulfate.
Secondly, the metal compounds in the water can react chemically with copper sulfate to reduce the toxicity. For example, the toxicity of copper sulfate is also reduced when the water contains salt or calcium chloride.
Another problem in the use of copper sulfate is that copper ions are easy to accumulate in the body, which can easily cause fish kidney necrosis, decrease hematopoietic function, reduce the activity of intestinal digestive enzymes, cause digestive system disorders, and even affect the growth of fish.
Tolerance of different fish species to copper sulfate
Different fish species have different tolerances to copper sulfate.
According to reports, the sensitivity of fish to copper sulfate is as follows: first, salmon, then grass carp, silver carp, then carp, crucian carp, and tilapia.
According to measurements, when the copper ion content in the water is 0.012 g/m3, the food intake of salmon fry is significantly reduced, and when it exceeds 0.017 g/m3, they stop eating.
When the copper ions in the water reach 5-10 micrograms per liter, the nitrogen fixation and photosynthesis of cyanobacteria and other organisms are inhibited.
Silver carp’s 50% avoidance concentration of copper sulfate is 0.3 g/cubic meter.
When the copper sulfate concentration is less than 0.5 g/cubic meter, it has no killing effect on fish parasites. When it exceeds 1 g/cubic meter, it can easily cause fish poisoning and death, reducing the safe concentration. The risk increases.
Application of copper sulfate in aquaculture
1. Prevent and treat fish diseases.
Copper sulfate can be used to prevent and control fish diseases caused by protozoa (such as flagellates, ovarian trichuriasis, cryptotrichuriasis, fish hyaline disease, trichomonassis, ciliates, ciliates such as trichozoa, etc.) and fish diseases caused by crustaceans (such as Chinese owl disease, etc.).
The concentration of the drug for splashing in the whole pool: It is often used in conjunction with ferrous sulfate, which is both safe and effective.
In spring and autumn, it is 0.7-1 g/cubic meter. The ratio of copper sulfate to ferrous sulfate is 5:2 or 6:2. When copper sulfate is used alone, it is less than 1 g/cubic meter.
In summer it should be reduced to 0.6~0.8g/cubic meter. When applying the medicine, try to spread it evenly throughout the pond. After using the medicine, make preparations to rescue the floating heads of fish.
Copper sulfate and potassium permanganate (5:2) are used in combination. When the water temperature is below 10 degrees, the concentration is 0.5-0.7 g/cubic meter to treat schistosomiasis.
The combination of copper sulfate and citric acid (3:2), with a pool water concentration of 0.15-0.20 g/cubic meter, can treat small melonworm disease.
Copper sulfate 0.7 g/cubic meter can treat ciliate disease in overwintering broodstock.
Copper sulfate 0.7g/cubic meter and 0.4g/cubic meter Prometryn are used together. First use copper sulfate, then mix Prometryn with wet soil (1:100) and then splash it to kill the green mud moss.
Copper sulfate 0.7 g/m3 can kill rotifers and snails when used once every 1 day; use once every 12 hours can kill field snails, lake snails, and red tide organisms in shrimp ponds (gynodinoflagellates, tridinoflagellates, etc.) ).
Copper sulfate 1 g/cubic meter can kill rotifers in water to prevent hypoxia caused by excessive reproduction of rotifers.
The combination of 0.5 g/cubic meter of copper sulfate and 1 g/cubic meter of rhubarb can treat bacterial diseases. If used again every 3-4 days, it can treat grass carp hemorrhagic disease.
2. Medicinal bath for fish (fry) seeds.
The commonly used medicinal bath concentration is a copper-iron mixture aqueous solution with a concentration of 8 grams/cubic meter (that is, the ratio of copper sulfate to ferrous sulfate is 5:2). Add 8 g/cubic meter of copper sulfate and 10 g/cubic meter of bleaching powder and take a medicated bath for 10-30 minutes. Both of the above formulas can kill bacteria and protozoa on the body surface and gills, and are also effective against myxocysts that have not formed cysts.
3. Kill algae plants and control the growth of harmful algae.
Copper sulfate can be used to inhibit and kill excessive cyanobacteria and filamentous green algae in ponds, and can also kill fungi and certain bacteria. Copper sulfate is effective in killing cyanobacteria and can also be used to prevent fish poisoning caused by Microcystis and Ovodinium. The concentration of the drug splashed in the whole pool is 0.7-0.9 g/cubic meter (the ratio of copper sulfate to ferrous sulfate is 5:2). Copper sulfate can also be used to remove green mud moss, snails, clams, etc. and to prevent fish, shrimp, and crab diseases caused by the attachment of filamentous algae.
It is advisable to start the aerator in time after taking the medicine, or add water as appropriate in the early morning of the next day. Prevent the toxic substances produced after algae death from causing fish poisoning or hypoxic pond flooding.
4. Disinfect tools and food places.
Use 20 grams/cubic meter of copper sulfate aqueous solution for fish gear disinfection for half an hour to kill protozoa.
Food court disinfection can be carried out regularly during fish disease epidemic seasons. Use 100 grams of copper sulfate and 40 grams of ferrous sulfate each time. Dissolve in water and then sprinkle it around the food court. Control the area to 80-100 square meters. Sprinkle the medicine first and then feed the fish. Use it once a day for 2 to 3 days. Used to prevent and treat protozoal diseases.
Things to note when using copper sulfate
1. Copper sulfate and ferrous sulfate have a synergistic effect. Ferrous sulfate itself has no insecticidal effect, but has an astringent effect, which can promote the penetration of the main drug into the body, increase permeability, and improve the efficacy of the main drug. Therefore, when using copper sulfate, it should be combined with ferrous sulfate as much as possible.
2. The safe concentration range of copper sulfate is small. Therefore, the toxicity of copper sulfate is difficult to control. Measurement of pool water volume and dosage must be calculated accurately. And make preparations for rescue operations such as adding water and adding oxygen in the event of a drug injury accident.
Because its safe concentration range is small, for freshwater fish, it should not exceed 1.0 g/cubic meter under normal circumstances. The normal effective dosage is 0.7 g/cubic meter. In production, 0.5 g/cubic meter of copper sulfate and 0.2 g/cubic meter of ferrous sulfate are commonly used. It not only improves the efficacy of the medicine but also reduces the risk of poisoning. Under normal circumstances, the concentration should be controlled at 0.7 grams per cubic meter of water. If the concentration is lower than 0.5 grams per cubic meter, the killing effect is poor. If the concentration is higher than 1 gram per cubic meter, fish may be in danger of poisoning and death.
3. Increase or decrease the dosage according to the water quality. If the water quality is relatively fertile and the water temperature is low, the dosage of pesticide can be appropriately increased; otherwise, the dosage of pesticide can be reduced. It should be no more than 1 g/cubic meter (some people have proposed to control it below 1.5 g/cubic meter. The dosage of copper sulfate used at low temperatures must be increased to 1~1.4 g/cubic meter as appropriate). At the same time, do not apply pesticides in the morning when fish are floating and when the water temperature is high at noon. It is best to use it between 4 and 6 p.m.
4. Because copper ions are easy to accumulate in the body and produce many side effects, they should be used with caution and cannot be used continuously. Heavy metals are toxic substances and can accumulate in fish bodies, thereby endangering human health. Therefore, they should be used as little or as little as possible in breeding. This is an issue that cannot be ignored and needs to be solved urgently in the production of green aquatic products in healthy breeding.
5. Copper sulfate aqueous solution is corrosive to metals and cannot be dissolved in metal containers. When dissolving copper sulfate, the water temperature should not exceed 60 degrees, otherwise it will easily fail.
6. Do not use copper sulfate immediately on ponds that have just been sprinkled with soy milk. Because the protein in soy milk can combine with copper sulfate, making the copper sulfate ineffective.
7. It is best not to use copper sulfate for scaleless fish such as catfish, channel catfish, etc. Because these fish are very sensitive to copper sulfate.
8. Copper sulfate cannot be used when the weather is hot and muggy, because not only is its toxicity greater than usual at this time, but the dissolved oxygen in the water is also low, and fish have poor resistance to toxicity. If they stay together, it will cause anoxic and dead fish accidents.
9. When used to kill blue (green) algae in water bodies, it is best not to splash a large amount throughout the pond. It should be used in small batches and multiple times. The best way is to concentrate the blue (green) algae in one corner (piece) when the wind blows it and splash it in that area. Otherwise, a large number of algae will die in a short period of time, and after decay, the water quality will be seriously damaged, causing hypoxia or poisoning.
Post time: Apr-15-2024