Why should we emphasize the use of quicklime in healthy farming?

The application of quicklime in healthy aquaculture has the advantages of safety, environmental protection and little side effects. However, in recent years, some farmers have "forgotten" the recognized ideal taste of quicklime for fear of "trouble" because it is more laborious and labor-intensive than "convenient" drugs. Here, the majority of aquaculture farmers are reminded to pay attention to the use of quicklime.

The main function of (1) quicklime

① pond cleaning: quicklime is a traditional pond cleaning medicine for aquaculture. Cleaning the pond with quicklime can not only kill parasites and pathogens in the pond, but also kill wild fish, snails, mussels, aquatic insects, tadpoles and other harmful organisms. It also has a strong killing effect on microcystis, cyanobacteria, green mud moss and some aquatic plants in water, and can improve soil and water quality.

② Water transfer: Aquatic animals like to live in neutral and weakly alkaline water. If there is a lot of silt in the pond, the amount of feeding is large, and the organic fertilizer is applied, the hardness of the water source is low, which is easy to cause eutrophication and the water quality is acidic. Spraying quicklime water all over the pond can adjust the acidic water quality and improve the hydroponic environment.

③ Fertilization: Calcium is deficient in water, so it is ideal to use quicklime as calcium fertilizer. Especially in the ponds where crustaceans such as shrimps and crabs are cultured, spraying quicklime water regularly can increase the calcium content in the water, which is beneficial to the formation of chitin in crustaceans.

④ Disease prevention function: quicklime has obvious sterilization and disinfection function. Spraying quicklime regularly before the popular season of fish, shrimp, crab and other cultured animals can prevent diseases; When bacterial diseases occur in fish, spraying quicklime can inhibit and relieve the disease and play a role in preventing and treating diseases.

⑤ Other functions: When the inlet and outlet pipes of the pond are buried, it is best to use quicklime as filler to block the gaps around the pipes. Mix quicklime with soil and fill it in the hole to form calcareous mud paste and make it firm. In rainy weather in summer, feed is very susceptible to moisture. In the feed warehouse, first spread a layer of quicklime at the bottom and a layer of snakeskin cloth at the top (for ventilation), and then pile up the feed, which can play a better moisture-proof effect.

(2) How to use quicklime

① pond cleaning and disinfection: generally, the cleaning amount of dry pond is 60 ~ 75kg/ mu. First, drain the pool water to a depth of 5 ~ 10 cm, then dig several small pits around the bottom of the pool, pour the quicklime into the pits, add water to dissolve it, and pour the limewater evenly into the pool while it is hot, which can quickly remove wild fish and shrimp, large aquatic organisms and bacteria. It is best to use a long-handled mud rake the next day. Wet pond cleaning, general water depth 1m, dosage 150 ~ 250kg/ mu, depending on the amount of silt at the bottom of the pond and the pH value of the soil.

② Disease control: In the epidemic season of bacterial gill rot, septicemia or eosinophilia, spray quicklime 15 ~ 25 kg per mu every month for 12 times. Quicklime 10 ~ 15 kg/mu can increase the pH value of pond water to 8.2 ~ 8.9, which can promote the simultaneous molting of cultured shrimp and avoid cannibalism. It can also increase dissolved oxygen in the pool water and reduce the number of harmful bacteria in the water. Spraying quicklime 5 ~ 10 kg/mu 1 ~ 2 times in the crab pond from May to September can prevent gill rot, shelling, diseases and moss growth of river crabs, and promote the molting and growth of young crabs.

③ Algicidal: When there are too many microcystis and cyanobacteria in the water of the culture pond, 5 ~15 kg of quicklime should be sprayed on the whole pond per mu of water surface; Or grinding quicklime into powder and spreading it evenly on moss (Spirogyra, Diptera, Phaeophyta, etc.). ) can make moss rot by roots.

④ Adjustment of water quality: Spraying 5- 10 kg of quicklime twice a month in the aquaculture pond can adjust the pH value of pond water, neutralize the acidity in the pond, improve the utilization rate of phosphorus by aquatic plants, promote the mineralization of organic matter and the decomposition of humus by anaerobic bacteria at the bottom of the pond, precipitate suspended particles in the water, increase transparency, and fatten the water quality, which is beneficial to plankton.

(3) Matters needing attention in using quicklime

Usage: After the quicklime is pulped, it must be sprinkled while it is hot. Avoid dumping residues into the pond to avoid fish eating by mistake, and do not throw whole lime into the pond for water disinfection. Because quicklime is easy to get wet, it should not be stored for too long, otherwise it will absorb moisture and carbon dioxide in the air and become powdered calcium carbonate, which will not play a role in sterilization. It is best to buy quicklime for aquaculture, and it is best to choose light blocks without impurities.

② Usage time: After sunny day 15: 00, it should be sprayed all over the pool to avoid the time when the water temperature is unstable in the morning and the water temperature is too high at noon. As the water temperature rises, the medicinal properties will be enhanced. When the water temperature is above 30℃ in summer, you should be careful to sprinkle quicklime on the aquaculture pond with water depth less than 1 m. If the weather changes suddenly, it is easy to cause floods. The use of quicklime should also avoid sultry and thunderstorm weather, otherwise it will cause the phenomenon of hypoxia and alkaline flooding.

(3) Conditions of use: Generally, intensive ponds are used, and the cultured animals feed and grow vigorously, so it is better to sprinkle quicklime frequently. Because there is no silt or little silt at the bottom of the newly dug pond, the buffering capacity is weak and the organic matter is insufficient, it is not suitable to use quicklime, otherwise it will aggravate the decomposition of limited organic matter, further reduce fertility and make it more difficult to improve water quality. Ponds with low pH value should be sprayed with quicklime for adjustment; Quicklime should not be used in ponds with high pH value and excessive calcium ions, otherwise the concentration of available phosphorus in water will be reduced, resulting in phosphorus deficiency in water and affecting the normal growth of phytoplankton.

④ Compatibility contraindications: quicklime is an alkaline drug and cannot be mixed with halogen drugs such as bleaching powder and strong chlorine essence. Because of bleach and so on. They are all acidic substances, and quicklime is alkaline after pulping. If mixed, acid-base neutralization will directly reduce the disinfection effect. Calcium lime cannot be used with trichlorfon at the same time. Trichlorfon is hydrolyzed with alkali to produce dichlorvos, which will increase its toxicity. Calcium lime can't be used with copper sulfate. At the same time, the hydroxide radical in water reacts with copper ions to generate water-insoluble copper hydroxide, and the efficacy of copper sulfate will be greatly reduced when used. Calcium lime can not be used with chemical fertilizer or ammonium nitrogen fertilizer at the same time, which is easy to cause ammonia poisoning in fish; If lime and phosphate fertilizer are used at the same time, the fertilizer efficiency of phosphate fertilizer will be reduced. Ponds with high alkalinity in saline-alkali areas should not be cleaned and disinfected with quicklime.