A method for hatching fish eggs and rearing fish fry using a rice field

Abstract

The application discloses a method for hatching fish fertilized eggs and cultivating fry in a rice field, which comprises the following steps of: rice field reconstruction, fertilized egg hatching, fry cultivation, feeding and fertilization, and fry catching; the fertilized egg hatching is performed by deepening the water level of the shallow ditch to 30-40 cm, fixing the fish nest with the fertilized eggs under the hatching frame, and placing the fish nest in the four corners of the rice field; after the fertilized eggs are hatched, the yolk fry falls on the dense mesh of the hatching frame, and then the fry swims away from the dense mesh; at this time, the hatching frame can be removed; the fry catching is performed by draining water to make the fry swim back to the collecting ditch, and then catching the fry by using a net; and the fry is caught according to the drainage of the rice field, so as to prevent the stress reaction caused by the hypoxia and high density; the rice planting, the fertilized egg hatching and the fry cultivation are all performed by using a natural method, the quality of the fry is good, the survival rate of the adult fish is high, the fry hatching facilities are greatly saved, and the output and the benefit of the rice field per unit area are obviously increased.

Description

Technical Field

[0001] This invention belongs to the field of agricultural technology, and specifically relates to a method for hatching fertilized fish eggs and raising fish fry in paddy fields. Background Technology

[0002] my country is a major aquaculture country in the world, with an annual aquaculture output exceeding 50 million tons. Therefore, a large number of fish fry are needed for aquaculture production each year. Aquaculture fry are produced through artificial breeding. The fertilized eggs need to undergo artificial incubation and fry rearing before they can be used for adult fish farming. The incubation of fertilized eggs and the rearing of fry are crucial steps in aquaculture production, and currently these key steps are generally carried out in ponds and hatching facilities.

[0003] To improve the hatching rate and production efficiency of fertilized eggs, intensive hatching methods are generally adopted to achieve high-density production under controlled conditions. Good hatching conditions result in high hatching efficiency and high fry production. However, due to the meticulous nature of this hatching method, some fry that should be culled are retained. These fry may have deformities, weak physiques, or congenital genetic defects, making them less resistant to environmental and disease factors. This leads to a relatively low survival rate in later stages of aquaculture, which is one of the factors contributing to the current severe outbreaks of aquatic fish diseases and causing serious losses to aquaculture production.

[0004] Historical and practical experience in aquaculture has shown that while the hatching rate of fish fry hatched under natural ecological conditions is relatively low, the quality of the fry is high, resulting in a high survival rate in later stages of rearing. Fish diseases are rare, reducing drug use and aquaculture costs, which is highly beneficial for aquaculture production. However, natural hatching inevitably occupies a large amount of ponds, leading to high production costs and impacting total yield; therefore, this method is rarely used for fish fry production. Furthermore, the rearing of hatched fry from fry to fingerlings is generally carried out in ponds or in factory-style facilities and equipment. This is because the initial stage of fry rearing requires high water quality and nutrients, necessitating the feeding of large quantities of highly nutritious feed. However, the fry's feed intake and digestion rates are lower than adult fish, often leading to rapid eutrophication of the water within a short period. This makes the fry susceptible to disease and mortality, requiring extensive water changes and water quality improvement, resulting in high energy consumption. Additionally, using fertilization to cultivate zooplankton as fry feed further exacerbates eutrophication, increasing the burden on wastewater treatment and the pressure on discharge. These breeding methods all require a large amount of manpower, material resources, breeding facilities, and pond area. Summary of the Invention

[0005] This invention provides a method for hatching fertilized fish eggs and raising fish fry in paddy fields. It can solve the problems of current fish hatching and fry raising processes, such as occupying a large amount of water surface and equipment, high energy consumption, and easy water pollution. This invention can carry out fish hatching and fry raising in paddy fields during the fish breeding season, thereby promoting rice growth, reducing fry breeding input, and improving product quality.

[0006] To solve the above problems, the technical solution provided by the present invention is as follows:

[0007] This invention provides a method for hatching fertilized fish eggs and raising fish fry in paddy fields, comprising the following steps:

[0008] Step 1, paddy field improvement: Select a paddy field with an area of ​​2 to 5 mu. In addition to raising the field ridges, dig a seedling collection ditch on one side of the paddy field. The ditch should be 0.6 to 2 meters wide and 40 to 100 centimeters deep. After the seedlings are planted, in order to ensure that the fish fry can swim back to the seedling collection ditch smoothly when collected, use a grooving tool to dig several shallow trenches with a triangular cross section from the seedling collection ditch into the field between the seedlings. The width of the shallow trenches should be less than the spacing between the seedling rows.

[0009] Step 2, hatching of fertilized eggs: Deepen the water level in the shallow ditch to 30-40 cm, fix the fish nests with fertilized eggs attached under the hatching rack, and place them around the perimeter of the paddy field, ensuring that the distance between the fish nests is more than two row spacings; after the fertilized eggs hatch, the yolk sac fry will fall onto the dense netting of the hatching rack. After the fry swim horizontally and leave the dense netting, the hatching rack can be removed.

[0010] Step 3, Fry rearing: Do not feed the fry for the first 5-7 days after they start swimming horizontally. After 7 days, feed them fine rice bran or wheat bran. Apply fermented chicken manure liquid fertilizer once every 7 weeks. The chicken manure liquid fertilizer is soaked before use, and the supernatant is dissolved with inorganic phosphate fertilizer or potassium fertilizer before application. Feed them in the fry collection ditch after 15 days. After 1-2 months of rearing, the fry can grow into summer fry. Feeding is done using a feeder.

[0011] Step 4, Fish Fry Harvesting: After being raised for 1 to 2 months, the fish fry can reach a body length of 5 to 15 cm and can be harvested for sale or for breeding into larger fish. When harvesting, drain the water to allow the fish in the paddy field to swim back to the collection ditch, and then catch them with nets. When catching, follow the excrement in the paddy field to prevent stress caused by lack of oxygen and high density.

[0012] In an optional embodiment of the present invention, the grooving device in step 1 includes a main board and multiple splitting blades; the main board includes a raised head and a rectangular plate surface, a triangular second cutting blade is provided at the back end of the plate surface, and a strip-shaped first cutting blade and multiple splitting blades are also provided on the back of the plate surface. The first cutting blade is perpendicular to the second cutting blade, the first cutting blade ensures that the plate surface moves in a straight line, the second cutting blade cuts the paddy field bottom mud into triangular strips, and then the splitting blades separate the paddy field bottom mud on both sides of the main board, thereby forming shallow trenches.

[0013] In an optional embodiment of the present invention, the grooving device in step 1 further includes a force-bearing arm, which includes a handle, a fixing rod, and a fixing frame. The fixing frame is fixed to the front end of the main board, the handle is fixed to the fixing frame, the fixing rod is at the rear end of the main board, and the fixing rod is also fixed to the handle. The position of the handle on the fixing rod is adjustable, thereby changing the angle of the handle to facilitate manual or mechanical operation.

[0014] In an optional embodiment of the present invention, the fish nest in step 2 is composed of palm flakes and netting.

[0015] In an optional embodiment of the present invention, the incubation rack in step 2 is used to place fish nests. The incubation rack includes a fixed frame, a dense net, and hooks. The fish nests are placed on the dense net. The fixed frame is a U-shaped beam structure. Hooks are provided on the fixed frame for fixing the fish nests. The dense net is fixed between the vertical bars on both sides of the fixed frame by screws. When not in use, the two are folded together. When in use, the fixed frame is opened, and the lower ends of the vertical bars of the fixed frame are inserted into the soil so that the dense net is parallel to and in contact with the bottom of the paddy field. The distance between the dense net and the beam of the fixed frame is maintained at 8-12 cm.

[0016] In one optional embodiment of the present invention, the number of fertilized eggs hatched per acre in step 2 is 200,000 to 300,000.

[0017] In an optional embodiment of the present invention, the feeder in step 3 includes a hopper, a water pump, a conduit, a vertical pipe ball valve, and a pressure valve. The hopper is used to hold soybean milk, rice bran or wheat bran suspension, or liquid fertilizer. A water pump is connected to the bottom of the hopper, and the water pump delivers liquid to the conduit. The end of the conduit is connected to a vertical pipe, the opening of which narrows. A float ball is inside the vertical pipe. When the liquid in the vertical pipe reaches the top, the float ball seals the opening, thus ensuring equal pressure and filling the pipe with liquid. Under the action of the water pump, the pressure inside the conduit increases. When the pressure reaches a certain level, it will open the pressure valve on the conduit, causing the liquid to spray out along the various pressure valves on the conduit, achieving uniform feeding or fertilization. The pressure valve is connected to the conduit.

[0018] In an optional embodiment of the present invention, the pressure valve includes a piston cylinder, a piston, a pressure spring, and a connecting pipe. The connecting pipe is connected to the piston cylinder, and the piston inside the piston cylinder is connected to the pressure spring. The liquid in the conduit transmits pressure to the piston cylinder through the connecting pipe, and the piston compresses the pressure spring. The piston cylinder has a hole on its wall. When the pressure inside the piston cylinder reaches a preset value, the hole on the piston cylinder is exposed, and the liquid is ejected.

[0019] Beneficial Effects: This invention provides a method for hatching fertilized fish eggs and raising fish fry in paddy fields, including paddy field modification, fertilized egg hatching, fish fry raising, feeding and fertilization, and fish fry harvesting. Fertilized egg hatching: The water level in the shallow ditch is deepened to 30-40 cm. Fish nests with attached fertilized eggs are fixed under the hatching rack and placed around the perimeter of the paddy field. After hatching, the yolk sac larvae fall onto the dense netting of the hatching rack. Once the larvae swim horizontally and leave the netting, the hatching rack can be removed. Fish fry harvesting: During harvesting, water is drained to allow the fish fry in the paddy field to swim back to the collection ditch, where they are then caught with nets. Harvesting is done according to the paddy field's excrement to prevent stress caused by oxygen deficiency and overcrowding. This invention uses natural methods for rice planting, fertilized egg hatching, and fish fry raising, resulting in high-quality fish fry and a high survival rate in adult fish farming. It significantly reduces the need for fish fry hatching facilities, resulting in a substantial increase in output and benefits per unit area of ​​paddy field. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments or prior art, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart illustrating a method for hatching fertilized fish eggs and raising fish fry using rice paddies, as provided in this application embodiment.

[0022] Figure 2 This is a schematic diagram of the troughing device structure used in a method for hatching fertilized fish eggs and raising fish fry in paddy fields, which is provided in an embodiment of this application.

[0023] Figure 3 This is a schematic diagram of the mainboard structure of a slotter provided in an embodiment of this application.

[0024] Figure 4 This is a schematic diagram of the segmentation structure of a slotter provided in an embodiment of this application.

[0025] Figure 5This is a schematic diagram of the incubation rack structure used in a method for hatching fertilized fish eggs and raising fish fry in paddy fields, as provided in an embodiment of this application.

[0026] Figure 6 This is a schematic diagram of the pressure valve structure of a feeder used in a method for hatching fertilized fish eggs and raising fish fry in paddy fields, as provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0028] like Figure 1 As shown, this embodiment of the invention provides a method for hatching fertilized fish eggs and raising fish fry in paddy fields, including paddy field transformation, hatching fertilized eggs, raising fish fry, feeding and fertilizing, and harvesting fish fry. It can carry out fish fry hatching and raising in paddy fields, thereby saving ponds, ecological seedling raising, promoting rice growth and achieving the purpose of fish fry raising.

[0029] The specific steps of a method for hatching fertilized fish eggs and raising fish fry using rice paddies are as follows:

[0030] Step 1, paddy field improvement: Select a paddy field with an area of ​​2 to 5 mu. In addition to raising the field ridges, dig a seedling collection ditch on one side of the paddy field. The ditch should be 0.6 to 2 meters wide and 40 to 100 centimeters deep. After the seedlings are planted, in order to ensure that the fish fry can swim back to the seedling collection ditch smoothly when collected, use a grooving tool to dig several shallow trenches with a triangular cross section from the seedling collection ditch into the field between the seedlings. The width of the shallow trenches should be less than the spacing between the seedling rows.

[0031] Step 2, hatching of fertilized eggs: Deepen the water level in the shallow ditch to 30-40 cm, fix the fish nests with fertilized eggs attached under the hatching rack, and place them around the perimeter of the paddy field, ensuring that the distance between the fish nests is more than two row spacings; after the fertilized eggs hatch, the yolk sac fry will fall onto the dense netting of the hatching rack. After the fry swim horizontally and leave the dense netting, the hatching rack can be removed.

[0032] Step 3, Fry rearing: Do not feed the fry for the first 5-7 days after they start swimming horizontally. After 7 days, feed them fine rice bran or wheat bran. Apply fermented chicken manure liquid fertilizer once every 7 weeks. The chicken manure liquid fertilizer is soaked before use, and the supernatant is dissolved with inorganic phosphate fertilizer or potassium fertilizer before application. Feed them in the fry collection ditch after 15 days. After 1-2 months of rearing, the fry can grow into summer fry. Feeding is done using a feeder.

[0033] Step 4, Fish Fry Harvesting: After 1 to 2 months of rearing, the fish fry will reach a length of 5 to 15 cm, ready for harvesting and sale or for larger-sized breeding. During harvesting, drainage is used to allow the fish fry in the paddy field to migrate back to the collection ditch, where they are then caught with nets. Harvesting is done according to the paddy field's excrement patterns to prevent stress caused by oxygen deficiency and overcrowding. In this embodiment, multiple excrement arrays are set up in the paddy field.

[0034] like Figure 2 , Figure 3 and Figure 4 As shown, the grooving device in step 1 includes a main board 1 and splitting pieces 2. The main board 1 includes a raised head 1-1 and a rectangular plate surface 1-2. A triangular second cutting blade 7 is provided at the back end of the plate surface 1-2. A strip-shaped first cutting blade 6 and multiple splitting pieces 2 are also provided on the back of the plate surface 1-2. The first cutting blade 6 is perpendicular to the second cutting blade 7. The first cutting blade 6 ensures that the plate surface 1-2 moves in a straight line. The second cutting blade 7 cuts the paddy field mud into triangular strips, which are then separated on both sides of the main board 1 by the splitting pieces 2, thereby forming shallow trenches. Each splitting piece 2 includes a right-angled side 2-1 and a hypotenuse 2-2.

[0035] The grooving device in step 1 also includes a lever arm, which includes a handle 5, a fixing rod 4, and a fixing frame 3. The fixing frame 3 is fixed to the front end of the main board 1, the handle 5 is fixed to the fixing frame 4, the fixing rod 4 is at the rear end of the main board 1, and the fixing rod 4 is also fixed to the handle 5. The position of the handle 5 on the fixing rod 4 is adjustable, thereby changing the angle of the handle 5 for convenient manual or mechanical operation.

[0036] like Figure 5 As shown, the fish nest in step 2 consists of palm fiber and netting. The hatching rack in step 2 is used to hold the fish nest. The hatching rack includes a fixed frame 8, a dense netting 9, and hooks 10. The fish nest is placed on the dense netting 9. The fixed frame 8 has a U-shaped crossbeam structure, and hooks 10 are installed on the fixed frame 8 to secure the fish nest. The dense netting 9 is fixed between the vertical bars on both sides of the fixed frame 8 by screws 11. When not in use, the two are folded together. When in use, the fixed frame 8 is opened, and the lower ends of the vertical bars of the fixed frame 8 are inserted into the soil, so that the dense netting 9 is parallel to and in contact with the bottom of the paddy field. The distance between the dense netting 9 and the crossbeam of the fixed frame 8 is maintained at 8-12 cm, preferably 10 cm. The hatching capacity of fertilized eggs per acre in step 2 is 200,000-300,000.

[0037] The feeder in step 3 includes a hopper, a water pump, a guide pipe, a vertical pipe ball valve, and a pressure valve. The hopper is used to hold soybean milk, rice bran or wheat bran suspension, or liquid fertilizer. A water pump is connected to the bottom of the hopper, and the water pump delivers liquid to the guide pipe. The end of the guide pipe is connected to a vertical pipe, which narrows at the opening. There is a float ball inside the vertical pipe. When the liquid in the vertical pipe reaches the top, the float ball will seal the opening, thus making the pipe pressure equal and full of liquid. Under the action of the water pump, the pressure in the guide pipe increases. When the pressure reaches a certain level, it will open the pressure valve on the guide pipe, causing the liquid to spray out along the various pressure valves on the guide pipe, achieving uniform feeding or fertilization. The pressure valve is connected to the guide pipe.

[0038] like Figure 6 As shown, the pressure valve includes a piston cylinder 12, a piston 13, a pressure spring 15, and a connecting pipe 14. The connecting pipe 14 is connected to the piston cylinder 12, and the piston 13 inside the piston cylinder 12 is connected to the pressure spring 15. The liquid in the conduit transmits pressure to the piston cylinder 12 through the connecting pipe 14, and the piston 13 compresses the pressure spring. The piston cylinder 12 has a hole 16 on its wall. When the pressure inside the piston cylinder 12 reaches a preset value, the hole 16 on the piston cylinder 12 is exposed, and the liquid is ejected.

[0039] Example 1

[0040] Five paddy fields, each 2.5 mu (approximately 0.16 acres), are used for hatching fertilized carp eggs and raising fry in paddy fields. The method described above is for hatching fertilized fish eggs and raising fry in paddy fields. Paddy Field Modification: Select paddy fields of approximately 2.5 mu each. In addition to raising the field ridges, dig a collection ditch on one side of the paddy field, approximately 1 meter wide and 50 cm deep. After the rice seedlings are planted, to ensure the fry can swim back to the collection ditch smoothly during collection, use a grooving tool to dig several shallow trenches with triangular cross-sections, starting from the collection ditch and extending into the field between the seedlings. The width of the trenches should be less than the spacing between the seedling rows. Fertilized Egg Hatching: Deepen the water level to 40 cm. Place fish nests (usually palm fiber or netting) with attached fertilized eggs under hatching racks around the perimeter of the paddy field, ensuring the distance between nests is at least two row spacings. The hatching rate is 200,000 to 300,000 fertilized eggs per mu.

[0041] Results: The average hatching rate of carp fertilized eggs reached over 90%, and the survival rate of fry reached over 95%. The fish were strong and healthy, and there were few diseases in the later stages of adult fish farming, which significantly increased the output and benefits per unit area of ​​paddy field.

[0042] Example 2

[0043] There are three paddy fields, each 5 mu (approximately 0.33 hectares) in size, with relatively good conditions. We plan to hatch fertilized crucian carp eggs and cultivate fry in these fields, following the technical scheme described above for using paddy fields for fish egg hatching and fry cultivation. Paddy Field Modification: Select paddy fields of approximately 5 mu (approximately 0.33 hectares). In addition to raising the field ridges, dig a collection ditch on one side of the paddy field, approximately 1 meter wide and 50 centimeters deep. After the rice seedlings are planted, to ensure the fry can swim back to the collection ditch smoothly during collection, use a grooving tool to dig several shallow, triangular-shaped trenches between the seedlings, starting from the collection ditch and extending into the field. The width of the trenches should be less than the spacing between the rows of seedlings. Fertilized Egg Hatching: Deepen the water level to 40 centimeters. Place fish nests (usually palm fiber or netting) with attached fertilized eggs under hatching racks around the perimeter of the paddy field, ensuring the distance between nests is at least two row spacings. The hatching capacity is approximately 300,000 fertilized eggs per mu (approximately 0.067 hectares).

[0044] Results: The average hatching rate of crucian carp fertilized eggs reached over 95%, and the survival rate of fry reached over 98%. The fish were strong and healthy, and there were few diseases in the later stages of adult fish farming, which significantly increased the output and benefits per unit area of ​​paddy field.

[0045] In summary, although the present invention has been disclosed above with reference to preferred embodiments, the above preferred embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope defined in the claims.

Claims

1. A method for hatching fertilized fish eggs and raising fish fry in paddy fields, characterized in that, Includes the following steps: Step 1, paddy field improvement: Select a paddy field with an area of ​​2 to 5 mu. In addition to raising the field ridges, dig a seedling collection ditch on one side of the paddy field. The ditch should be 0.6 to 2 meters wide and 40 to 100 centimeters deep. After the seedlings are planted, in order to ensure that the fish fry can swim back to the seedling collection ditch smoothly when collected, use a grooving tool to dig several shallow trenches with a triangular cross section from the seedling collection ditch into the field between the seedlings. The width of the shallow trenches should be less than the spacing between the seedling rows. Step 2, hatching of fertilized eggs: Deepen the water level in the shallow ditch to 30-40 cm, fix the fish nests with fertilized eggs attached under the hatching rack, and place them around the perimeter of the paddy field, ensuring that the distance between the fish nests is more than two row spacings; after the fertilized eggs hatch, the yolk sac fry will fall onto the dense netting of the hatching rack. After the fry swim horizontally and leave the dense netting, the hatching rack can be removed. Step 3, Fry rearing: Do not feed the fry for the first 5-7 days after they start swimming horizontally. After 7 days, feed them fine rice bran or wheat bran. Apply fermented chicken manure liquid fertilizer once every 7 weeks. The chicken manure liquid fertilizer is soaked before use, and the supernatant is dissolved with inorganic phosphate fertilizer or potassium fertilizer before application. Feed them in the fry collection ditch after 15 days. After 1-2 months of rearing, the fry can grow into summer fry. Feeding is done using a feeder. Step 4, Fish Fry Harvesting: After being raised for 1 to 2 months, the fish fry can reach a body length of 5 to 15 cm and can be harvested for sale or for breeding into larger fish. When harvesting, drain the water to allow the fish in the paddy field to swim back to the collection ditch, and then catch them with nets. When catching, follow the excrement in the paddy field to prevent stress caused by lack of oxygen and high density. Step 1 The grooving device includes a main board and multiple splitting blades; the main board includes a raised head and a rectangular plate surface, a triangular second cutting blade is provided at the back end of the plate surface, and a strip-shaped first cutting blade and multiple splitting blades are also provided on the back of the plate surface. The first cutting blade is set perpendicular to the second cutting blade. The first cutting blade ensures that the plate surface moves in a straight line. The second cutting blade cuts the paddy field bottom mud into triangular strips, and then the splitting blades separate the paddy field bottom mud on both sides of the main board, thereby forming shallow trenches.

2. The method for hatching fertilized fish eggs and raising fish fry using paddy fields according to claim 1, characterized in that, The grooving device in step 1 also includes a force arm, which includes a handle, a fixed rod, and a fixed frame. The fixed frame is fixed to the front end of the main board, the handle is fixed to the fixed frame, the fixed rod is at the rear end of the main board, and the fixed rod is also fixed to the handle. The position of the handle on the fixed rod is adjustable, thereby changing the angle of the handle for convenient manual or mechanical operation.

3. The method for hatching fertilized fish eggs and raising fish fry using paddy fields according to claim 1, characterized in that, The fish nest in step 2 is made of palm flakes and netting.

4. A method for hatching fertilized fish eggs and raising fish fry using paddy fields according to claim 1, characterized in that, The incubation rack in step 2 is used to place fish nests. The incubation rack includes a fixed frame, a dense net, and hooks. The fish nests are placed on the dense net. The fixed frame is a U-shaped crossbeam structure. Hooks are provided on the fixed frame to fix the fish nests. The dense net is fixed between the vertical bars on both sides of the fixed frame with screws. When not in use, the two are put together. When in use, the fixed frame is opened and the lower end of the vertical bar of the fixed frame is inserted into the soil so that the dense net is parallel to and in contact with the bottom of the paddy field. The distance between the dense net and the crossbeam of the fixed frame is maintained at 8-12 cm.

5. A method for hatching fertilized fish eggs and raising fish fry using paddy fields according to claim 1, characterized in that, In step 2, the hatching rate of fertilized eggs per acre is 200,000 to 300,000.

6. A method for hatching fertilized fish eggs and raising fish fry using paddy fields according to claim 1, characterized in that, The feeder in step 3 includes a hopper, a water pump, a conduit, a vertical pipe ball valve, and a pressure valve. The hopper is used to hold soybean milk, rice bran or wheat bran suspension, or liquid fertilizer. A water pump is connected to the bottom of the hopper, and the water pump delivers liquid to the conduit. The end of the conduit is connected to a vertical pipe with a narrow opening. A float ball is inside the vertical pipe. When the liquid in the vertical pipe reaches the top, the float ball seals the opening, thus ensuring equal pressure and filling the pipe with liquid. Under the action of the water pump, the pressure inside the conduit increases. When the pressure reaches a certain level, it will open the pressure valve on the conduit, causing the liquid to spray out along the various pressure valves on the conduit, achieving uniform feeding or fertilization. The pressure valve is connected to the conduit.

7. A method for hatching fertilized fish eggs and raising fish fry using paddy fields according to claim 6, characterized in that, The pressure valve includes a piston cylinder, a piston, a pressure spring, and a connecting pipe. The connecting pipe is connected to the piston cylinder, and the piston inside the piston cylinder is connected to the pressure spring. The liquid in the conduit transmits pressure to the piston cylinder through the connecting pipe, and the piston compresses the pressure spring. The piston cylinder has a hole on its wall. When the pressure inside the piston cylinder reaches a preset value, the hole on the piston cylinder is exposed, and the liquid is ejected.

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