Fish seedlings are one of the key technical aspects for raising the survival rate of seedlings during the fry cultivation process. Because of the delicate body, fry has strict requirements on the weather, water temperature, water quality, predators, and stocking operations. The farmers are slightly neglected. If it is not enough, the fry will be killed in different degrees, and the entire breeding process will fail. Here, the technical points of fish seedlings are summarized in ten aspects for reference.
First, check the clear pond effect. In the days from the first day to the second day of the fish ponds, the empty ponds should be pulled several times with a dense mesh to check whether there are any predator organisms in the ponds. For example, wild fish, frog eggs, cockroaches, aquatic insects and other predators should be re-cleared. Ponds, while pulling the net, can also allow the remaining pond clearing ponds to be fully dissolved to prevent damaging the fry.
Second, check the residual drug in the pond. If the toxicity of the drug has not completely disappeared, it may lead to poisoning and death of fish in the pond. The inspection method is: take half a barrel of bottom water, test the fish in the bottom water, or place the fry in a small cage in the pond, observe for 8 to 12 hours to determine whether the fry can enter the pool; The pH of the pool of water that can be measured, such as a pH of 8.5 or less, indicates that the toxicity has disappeared and the fish can be released; observation of pool water, if any, may indicate that the toxicity has disappeared.
Third, check the pool of fat. It is mainly based on the color of water, transparency and the number of food organisms. When the fish fry under the pond, the pool water is grayish-white, yellow-green or light yellow, and the transparency is 30 cm to 35 cm. Each liter of water contains about 10,000 rotifers, and the biomass is 20 mg to 30 mg per liter. If the pool water is not fat enough, the fish will grow poorly due to lack of feed. So the compost should be composted or poured into the pool corner of Xiangyang to fertilize the water immediately. When it is found that the water quality is too fat, it should be diluted with water and then put the fish. For example, if the base fertilizer of the pond is too early and the peak of rotifers has passed, excessive zooplankton such as blisters will be generated in the pool water, which will inhibit the reproduction of small zooplankton of the fry, and interfere with the activity and feeding of the fry. 0.3-0.5ppm crystal trichlorfon can be used. The pool is spattered to kill, and fish fry can be released after 1 to 2 days, or 300 to 400 tail fish species of more than 13 cm per acre are allowed to eat large zooplankton. At the same time, it can be judged whether or not the pond water is fat enough to be floated before the dawn, but the fish should be caught before the fry is released.
Fourth, timely pond. Fry hatching from 4 days to 5 days shows two eye spots and one waist point. When swimming normally in the water, it should be passed through the pond in time. When entering the pool too early, the fry is too tender and it is easy to sink into the sediment to cause death. If it is too late, it will affect the growth of the fry and the survival rate is low.
Fifth, stocking specifications should be consistent. The fry stocked in the same pond should be of the same variety and the same specifications, and should be enough to prevent the big fish from suppressing or eating small fishes and the appearance of irregularities.
Six, adjust the water temperature. When fish fry ponds, the temperature difference between the pool water and the fry container must not exceed 3°C. If the temperature difference is too large, it is necessary to gradually adjust the fry before adapting to the pond. For fish fry transported in plastic bags, the plastic bag should be opened first and slowly placed in a cage pre-placed in the fish pond until the water temperature in the pool is the same as that in the bag, so that the pool water is gradually mixed with the water in the bag. Minutes later, the fry and water are slowly poured into the cage, so as to adjust the temperature difference and the adaptability of the fry to the air pressure inside the bag, that is, “slow seedlingsâ€. If the fry is directly poured into the pool from the bag, the mortality of the fry is very high.
Seventh, the fry should be eaten before the next pond. The fry can be fed with egg yolks before the lower pond and one hen per 100,000 fry. The method is to fully cook the eggs or duck eggs, remove the egg yolk, use double gauze wrapped in the water, knead the egg yolk and splash it on the fry, and feed the yeast or rotifer. Insist on fry eating satiety pond, the survival rate can be significantly improved.
8. Choose the appropriate time, place and method of restocking. Fry stocking should try to choose sunny noon or afternoon, when the water temperature is high, dissolved oxygen is sufficient, is conducive to quickly return to normal activities after the fish pond, should avoid windy windy weather or night into the pool. In the windy days, the seedlings should be placed on the top of the deep water to avoid the large number of deaths caused by the stormy fish fry blowing to the pool or pressing to the bottom of the pool. When raising the seedlings, slowly tilt the container of fish fry into the water and let the fry slowly swim out of the water or pull the seedling container back slowly. Do not pour the fry into the pool. In addition, do not leave the fish fry immediately after entering the pool, and wait until the fry spread into the pool and then leave. If the fish seedlings are found to be densely integrated, they should be splashed with water droplets to spread them into the pool.
Nine, the depth of the pool is appropriate. Requires the pool water to be 40 cm to 50 cm deep, so that the temperature of the sun is easy to increase, the light is sufficient, the water quality is easy to fertilize, and the food organisms reproduce quickly, which is conducive to the rapid growth of fry.
Ten, stocking density appropriate. The fry were bred into Wuzi pools, and generally 200,000 to 250,000 tails of carp fry or grass carp, herring and carp seedlings were planted from 150,000 to 200,000. Such as fry bred into summer pool, then put 100,000 to 150,000 tail per mu, or grass carp, herring 80,000 to 100,000 tail.
We may have ever seen the PTZ Camera/ PTZ Camera Outdoor/ PTZ Webcam HD/ PTZ Camera Night Owl/ PTZ Network Camera/ Pan Tilt Zoom Outdoor Network Camera in our daily life, but can't recognize it or don't know its name. Today let me introduce the PTZ Camera for you. PTZ Camera refers to the camera with the PTZ, so what is the PTZ?
What is the PTZ?
PTZ, the abbreviation of Pan/ Tilt/ Zoom, is the supporting equipment for installing and fixing cameras. PTZ can be divided into two types: the Fixed PTZ and the Electric PTZ. The Fixed PTZ is suitable for the situations where the surveillance range is not large. After the camera is installed on the fixed pan/tilt, the horizontal and tilt angles of the camera can be adjusted. After reaching the best working posture, just lock the adjustment mechanism. Motorized PTZ is suitable for scanning and monitoring a large area, it can expand the surveillance range of the camera. The high-speed attitude of the electric pan/tilt is realized by two executive motors, and the motors receive signals from the controller to operate and position accurately. Under the action of the control signal, the camera on the PTZ can automatically scan the surveillance area, and can also track the surveillance object under the control of the staff on duty in the surveillance center.
The classification of the PTZ
According to the characteristics of the PTZ's rotation, the PTZ can be divided into the horizontal rotating PTZ that can only rotate left and right, and the all-round PTZ that can rotate not only left and right but also up and down. Generally speaking, the horizontal rotation angle is 0°~350°, and the vertical rotation angle is +90°. The horizontal rotation speed of the constant-speed PTZ is generally 3°~10°/s, and the vertical speed is about 4°/s. The horizontal rotation speed of the variable-speed PTZ is generally 0°~32°/s, and the vertical rotation speed is about 0°~16°/s. In some high-speed camera systems, the horizontal rotation speed of the PTZ is as high as 480°/s or more, and the vertical rotation speed is more than 120°/s.
In fact, the PTZ, composed of two AC/DC motors, is an installation platform, which can move horizontally and vertically. The PTZ applied to the monitoring system can be controlled the direction of rotation and movement remotely through the control system, which is different from the PTZ( just a tripod, which can only be adjusted by hand) in the photographic equipment.
In conclusion, I hope that the introduction about the PTZ can help you better understand the PTZ Camera.
In conclusion, I hope that the introduction about the PTZ can help you better understand the PTZ Camera.
PTZ Camera, PTZ Camera Outdoor, PTZ Webcam HD, PTZ Camera Night Owl, PTZ Network Camera, Pan Tilt Zoom Outdoor Network Camera
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