Construction method of Leech Farm

Leech in history to natural fishing mainly, due to recent years, pesticides, fertilizer abuse and industrial and agricultural "three wastes" pollution to the environment, wild natural resources sharply reduced, China began to catch natural seedlings around 1995, the first artificial breeding and success, the northern region because of seedlings and technical reasons has not been cultured, let's take a look at leech farm construction method!

leech farm selection

1, farm site selection: leech breeding pond should be sheltered from the sun, convenient drainage, water system, easy to escape, construction should be adapted to local conditions, general length is not limited, the best water surface width of about 3 meters. Continuous pool, connected pool ridge common, pool ridge width 1.5~2 meters, height 1.5 meters or so, can also be increased according to the amount of waste soil.

2. Culture pond excavation: a rectangular pond with unlimited length, width of 8 meters and depth of 0.3 meters shall be excavated for a single pond, and the waste soil shall be surrounded as a pond ridge. According to the longitudinal direction of the pool, dig a small ditch with a width of 0.7 m and a depth of 0.7 m at the center of two meters near the two sides of the pool, which is a deep water area. The waste soil is piled in the middle of the pool and piled into an island in the pool with a bottom width of 1.5 m and a sector section according to the same direction as the small ditch.

Construction of leech culture pond

1. Anti-escape net setting: level the surrounding pool ridge in time to prevent natural enemies from entering in advance. Anti-escape net should choose 30~50 mesh polyvinyl chloride mesh cloth, should be buried in the pool ridge, underground part should be more than 0.2 meters, the upper end folded inward 0.1~0.2 meters, wrapped in the net seam solid, fixed with wooden piles. If the upper end of the net is less than 1 meter away from the ground outside the net, the net below 30 meshes can be raised to prevent natural enemies such as snake babies from entering.

2. Deep-water habitat dock: a leech deep-water habitat dock is alternately built every 5 meters on the inner and outer sides of the deep-water area around the leech pool. Dig a deep pit slightly larger than the tile at the edge of the deep shallow water transition step with a shovel. Pay attention to shoveling a slope of about 30 degrees near the shallow water area, that is, near the pool ridge, and then stack the tiles along the slope from bottom to top. There should be a gap between the tiles. Generally, the front side and the front side, the back side and the back side will produce gaps. The advantage of placing the tiles according to the slope is to provide a climbing platform for leeches to enter the nest.

3. Zhongdao Habitat Dock: Dig a groove about 0.6 meters wide horizontally in the center island every 7.5 meters in the middle of the pool. The bottom of the groove is about 0.5 meters away from the bottom of the deep pool. Then put the tiles side by side vertically on both sides of the groove, leaving a gap of about 0.2 meters in the middle. Finally, lay a layer of bricks on the tiles, build a bridge, return the soil on the bricks, restore the original appearance, and the Zhongdao Habitat Dock will be built.

4, water treatment: water inlet diameter of 0.25 meters available hard clinker pipe, nozzle should be higher than the water surface, to prevent leeches escape. Overflow can also be used 0.25 m diameter hard clinker pipe. The water pipe is buried horizontally under the pond ridge, one end is in the deep groove in the deep water area of the pond, and the other end extends out of the pond, maintaining a horizontal position. At one end of the pool, install a 90-degree elbow joint with the opening upward, and then connect it with another 1-meter straight pipe. It is appropriate to measure the depth of shallow water area 0.3 meters after water is filled in the pool, otherwise, adjust the length of 1-meter pipe until it is appropriate. Install 50 mesh escape net at overflow pipe mouth.

5. Construction of egg bed: When the overflow port overflows, the water level in the shallow water area should be 0.3 meters deep. At this time, the soil of the island should be leveled with a shovel, and the surface close to the water should be leveled into a slowly rising slope, which is convenient for leeches to lay eggs on the island. The island will also become a natural egg bed for leeches. The middle part of the middle island should be 0.5 meters above the water surface. The inner side of the ridge around the pool should also be shoveled into a slope. At a place 0.2 meters high from the water surface, a platform at least 0.2 meters wide can also be made into a spawning bed.

Disinfection of leech culture pond

1, quicklime disinfection: select a few points in the bottom of the pool to put quicklime, the dosage is about 100 grams per square meter. Pond water 10~20 cm deep, to be limed open, with a ladle lime slurry will be poured into the pool. After a while, mix the lime slurry and water evenly. After clearing the pond for about 1 week, inject new water again, and then put leech seedlings. Using quicklime to disinfect the pond can not only kill parasites, germs and other harmful organisms in the pond, but also keep the pond water fresh to a certain extent, improve the soil quality, and release nutrients such as nitrogen, phosphorus and potassium in the bottom of the pond to increase the fertility of the water.

2, bleaching powder disinfection: bleaching powder clear pool disinfection, 5~10 kg per mu pool surface. Such as disinfection with water, water depth 0.5~1 meters, the amount of bleaching powder used to double, that is, 10~20 kg per mu pool surface, the whole pool splash. Bleaching powder releases hypochlorous acid when it meets water. The new ecological oxygen released by hypochlorous acid can kill harmful organisms such as germs. Its effect is similar to quicklime, but the drug disappears faster than quicklime. Generally, after 3~5 days of disinfection with bleaching powder, leeches can be put into the pond for breeding.

3, cement pool dealkalization: the newly built cement pool, the surface has a strong absorption of oxygen, can reduce the dissolved oxygen in the water, the pH value rises (alkaline), the formation of excessive calcium carbonate precipitate. In order to create a good growth environment for leeches, it is necessary to dealkalize the newly built cement pool before use. The following methods are generally used.

① Calcium superphosphate method: After the newly constructed cement pool is filled with water, calcium superphosphate is added according to the proportion of 1 kg per cubic meter of water, and the pool is immersed for 1~2 days. After the old water is drained and replaced with new water, seedlings can be put in.

② Acid sodium phosphate method: After the newly built cement pool is filled with water, dissolve 20 grams of acid calcium phosphate per cubic meter, soak for 1~2 days, and then put seedlings after replacing new water.

③ glacial acetic acid method: the new cement pool can be washed with 10% glacial acetic acid on the surface of the cement pool, then soaked in water for about 1 week, and seedlings can be put in after replacing new water.

4 potato alkali removal method: if the construction of a small area of cement pool, urgent need for treatment and no such drugs, can be used sweet potato, potato and other potatoes wipe the pool wall, so that starch paste stuck to the pool surface, and then filled with water soak for 1 day can be alkali.