Breeding method of arowana
Arowana is native to Amazon River Basin in South America, Nile River Basin in Africa, Australia and Papua New Guinea. Generally, they live in ponds of tributaries and submerged bushes on the shore, and sometimes they can be found in water environment with floating grass. After flowing into China, arowana has been successfully propagated in the south, and it is one of the main ornamental fish in China. Arowana is quite popular in Southeast Asia because of its feng shui demand.
Arowana is long and flat, with a fan-shaped tail, and its dorsal fin and anal fin are strip-shaped and extend backward to the base of the tail stalk. The lower jaw is more prominent than the upper jaw and has a pair of short and thick beards.
Its wide fish body is neatly arranged with five rows of large scales, shining silver in the light. Each fin reflects a bright red or orange luster under the light. The body color of young fish is blue; Both dorsal fin and anal fin have red and blue edges. The scales of Jinlong are golden, and all the fins are golden red. The body color of the red dragon is golden yellow, the scales are golden red, there are dark red spots on the mouth and gill cover, and all the fins are dark red. The body of the silver dragon is silvery white, the body of the black dragon is silvery white and purplish blue, and all the fins are blue black. Arowana can reach 50 ~ 100 cm in length.
The silver belt has a very slender body shape. The position of the mouth is above, and the fissure extends to the posterior edge of the orbit. The lower jaw protrudes from the upper jaw, and several linear lateral devices are arranged side by side in front. There are a pair of tentacles on the snout. The tentacles of adult fish can grow to 3-4cm in wild individuals swimming in the natural environment, but only to 1-2cm in artificially raised individuals. The odontoid bone of the mandible is well developed, and the conical teeth arranged like a comb between the upper and lower jaws are very small and sharp, and the tooth spacing is very narrow. Not only the anterior maxilla, but also the accessory sphenoid bone and hyoid bone of odontoid joint are very developed, which can bite large crustaceans and beetles. In addition, compared with the bite force of teeth, the upper and lower jaws pay more attention to the hunting function of easily catching prey. The gill harrow develops into a thorn. Gollum's big eyes are close to the front of the palate, and his vision is very good. The kiss is short. The nostrils are located in the front and upper parts of the eyes, very close to the nose and mouth. Both dorsal fin and gluteal fin are very long, and the starting point of gluteal fin is more forward than dorsal fin. The first spine of the stretched ventral fin even exceeds the starting point of the gluteal fin. The pectoral fins are well developed. In particular, the long and powerful first thorn is a sharp weapon for the silver belt to jump out of the water. This wonderful flying power made the silver belt win in South America? Jump fish? (Amazon? Water monkey? It's easy to jump at night, so add more protective nets. ) laudatory name.
The side of the body is covered with five rows of big and beautiful round scales. The lateral line runs from the top of the posterior margin of the head gill cover to the tail stalk. The body height is about one fifth of the body length. The male fish between five and eight years old, about 90cm, is much taller than the female fish.
Silver is skillfully mixed in the gray-green body. If krill is fed in larval, sub-adult and adult stages, red horizontal bands will be embedded in dorsal fin and gluteal fin due to the action of carotenoids, and even the outer edge of scales on one side of the conjoined body will turn red. As a fish, the red color gradually becomes lighter and becomes smoked silver and platinum. The white taste on the edge of dorsal fin and gluteal fin is stronger, which makes the already huge body bigger. Due to gender differences, the female fish is slightly darker and looks darker. On the other hand, the back is grayish green regardless of gender, which is very comfortable as the background color. However, the strong mirror image phenomenon on the side of the body makes it difficult to distinguish the female fish except the breeding period under the light. There are also a few individuals with albinism so-called white, gold and silver bands in the cultured individuals.
Growth and reproduction of arowana
Arowana ovulates and ejaculates in swimming. The diameter of eggs is about 4 mm, and each pair of parent fish lays about 200 eggs at a time, and more than 300 eggs. Under natural conditions, male and female arowana lay eggs in after ejaculation, and the male fish will hatch all fertilized eggs in his mouth. It takes about 40-60 days for fertilized eggs to hatch into larvae with yolk sacs. After living on the yolk sac for about 8 days, the larvae can develop into young fish that can swim and eat.
Breeding method of arowana
Breeding skills
Strong physique, rapid growth, big appetite. Fierce temperament, can swallow small fish, not mixed with other fish. Use a large fish tank with a cover and no bottom sand. I like weak acid or neutral soft water, the water temperature is above 22℃, and 24-28℃ is the most suitable. Mainly feed on animal bait. (Arowana is afraid of cold, pay attention to the water temperature)
Seedling preparation
At low temperature, doors and windows should be closed, and the temperature of fish house should be controlled at 28℃.
Choose a fish tank. A fish tank with a general diameter of 126 cm and a depth of 48 cm can be used for stocking 300 fry, packing filter cotton, activated carbon, coral stone, air pump and water pump, and controlling the water depth of the fish tank to 20 cm and the temperature to 28℃. At the same time, prepare an appropriate amount of fresh water, the water temperature is 25℃, the salt content is 1%, and furacilin is 2 mg/kg.
New fish in the fish tank
Newly bought fish, the air pump in the fish tank will take at least 24 hours to completely eradicate chlorine in the water. If the biofilter is used all the time, it is best to make the water reach PH 6-7 and the water temperature is 25 degrees Celsius. Add a small amount of salt (about 1 or 2 teaspoons in every 5 gallons or 20 liters of water) to the fish tank to reduce the risk of fungal attack, make the fish healthy and stimulate the appetite. If possible, it is best to take the water from the original tank of the new fish back to its aquarium (if there is no problem with the water in the original tank), and it is best to take it back to 1/3, which is conducive to the adverse reaction of the new fish to environmental mutation. It is recommended to raise arowana from an early age.
Fish tank size
Because arowana is a large fish, the fish tank is at least 1.5m long, 0.5m wide and 0.7m high. The fish tank must be covered. Arowana belongs to the upstream fish and likes to jump, so as to avoid choking when no one jumps out of the tank.
Feeding and taming
The newly introduced young arowana has 1 yolk sac, which is mainly nourished by yolk. The yolk sac disappears after 7 days, so it needs to be domesticated from the next day to meet its nutritional needs. It can be used to train blood-activating worms (soaked in 3% salt and 5 g/L nitrofurazone water solution 15 minutes before feeding). The operation should be very careful, and the feeding takes 20 minutes.
Timely replacement of materials
Young arowana is mainly fed with blood-activating worms within 65,438+00 days, and can be fed with quick-frozen blood worms after 65,438+00 days, and gradually transformed into shrimps in the third month (both seawater and freshwater shrimps can be cut into appropriate sizes after the head and tail are removed, and then washed with salt water and fed). Feeding time and frequency: feed 5 times a day, 4 times in the second month, 3 times in the third month and 2 times in the fourth month from 5: 00 a.m. to 5: 00 p.m. 1 0. Pay attention to remove the residue and bait 20 minutes after each feeding.
Adjust density
Arowana grows faster, with a body length of about 6 ~ 7 cm when it first enters fry, and it can grow to 65,438+02 cm at 65,438+0 months, 65,438+07 cm at 2 months and 24 cm at 3 months. Therefore, during its growth, the stocking density must be adjusted in time according to the growth situation, and it is best to screen 1 month/time. For the first time 1 time 150 heads per can, for the second time, 70 heads per can, and for the third time, 25 heads per can. After that, the stocking quantity will gradually decrease, or it will be moved to large tanks.
Water body management
The suitable water level of Yinlong fish tank is 1 20 cm per month, 25 cm in February, 30 cm in March, and 35 ~ 40 cm later. According to the different water quality, suck 1 time every 3-5 days in 1 month, and suck 1 time every day from the second month, and the water level shall not exceed 5cm each time. Clean filter cotton, activated carbon, etc. Every 5 ~ 7 days 1 time. During the whole feeding process, the pH value, dissolved oxygen and temperature of water should be strictly controlled. PH value is 6.8 ~ 7.2, dissolved oxygen is 7 mg/L, and temperature is 28℃. Once the water body is found to have adverse changes, corresponding measures should be taken immediately to adjust it.
growth cycle
grow up
Arowana takes a long time to grow and mature. Generally, it takes 6- 12 years for females and 5- 16 years for males (depending on your reproductive level). And not all arowana can breed in the aquarium like arowana. Arowana mainly breeds in aquariums, including Silver Dragon, Red Dragon (which is difficult and has not been successfully reported in China), Qinglong, Australian Arowana and so on. Arowana, like cichlids, are both oral fish and natural mating fish. In nature, arowana will hatch eggs in its mouth when it breeds. After hatching, the male will look after the young. When the enemy attacks or is frightened, the parent fish will hold the larvae in their mouths until the danger passes. This will continue until the larvae can feed themselves.
From 65438 to 0966, Mr. Miyata and Shiro Tanaka of Japan used hot spring water and self-designed steel refined concrete sink to complete the first aquarium culture of arowana. So far, they have a considerable number of breeding in the farms in Asu hot spring area. So how to breed arowana in an aquarium? First of all, the water body of arowana culture should be wide, and the better culture box should be more than 2 meters and 200 meters. 90? 60 or 250? 100? 60 sinks will do.
Parent fish preparation
Because arowana has its own pairing habits, it doesn't like people to match them artificially. Therefore, several young fish can be raised together and paired freely from an early age (5-7 years old). You can also put mature fish, one female and one male, on both sides of a large sink, separated by partitions, and holes must be made in the partitions to facilitate the flow of water on both sides. Fish will adapt to the environment here. When the arowana is in heat, it will pull open the partition. At this time, they will catch up with each other and then bite each other's fins, especially from the gluteal fin to the caudal fin. Arowana will be frightened and jump, or collide, and even cause beard to break and bleed. This kind of injury will not pose a threat to the life of arowana in a short time, so everyone should be patient. After a few days, if the two arowanas start to calm down and swim slowly, it means that the pairing is successful. If you are still struggling, it means that the matching is unsuccessful. You should check whether the matching fish is immature. Is there anything in the water that shouldn't be there? Then raise them separately and then pair them. Distinguish mature males from females: males generally like to show off in front of females. The most important thing is that the male fish is slender and the pectoral fin is very long and dark red. The abdomen of the female fish is full and swollen because of the eggs. The fallopian tubes of female fish protrude during spawning. The vas deferens of male fish are concave. These are all differences.
Water quality management
Paired arowana will be injured, so water quality management is extremely important in aquaculture.
1. Be careful not to over-feed, and the remaining bait must be taken out in time.
2. When there are signs of illness, you should immediately take a medicated bath and pay attention to prevent other fish from being infected. Because arowana is extremely sensitive to drugs, the dosage is much less than usual, which we will mention in the disease of arowana. Pay attention to changing water more than usual during the medicated bath.
3. Keep the pH value at 6.2-7.2 to prevent hyperacidity, and the water temperature is 26-28 degrees Celsius. When you do this, you see the close arowana couple together and stop at the bottom of the aquarium, which is their choice of spawning place. Find something to hide from the light. This will make it more secure and easier to lay eggs. Seeing the male fish put the eggs in his mouth, he can wait patiently for the young fish to hatch. When the male fish takes care of the eggs, the female fish will be there. After about 60 days, the fry will come in and out of the male's mouth.
The parent fish will slowly release the young fish, showing great care. This will last about 90 days. Little fish will go in and out of dad's mouth less. At this time, you can quietly fish out the small fish, and be patient when fishing, because other little guys will definitely hide in the fish father's mouth for a long time, so you can wait slowly. Male fish usually contain 40 eggs, but in the end there will only be a dozen small fish. It can be seen that the reproduction of arowana is really not easy. The parent fish will stop eating before spawning and will not eat until the young fish leave the male fish, so it is extremely harmful for the male fish to spawn and reproduce once. If the breeding before breeding is not good enough, the male fish will collapse or even die, so should we pay attention to the existence before breeding? Feeding preparation. The experiment of artificial hatching of fish eggs has not progressed, and the male fish still has to work hard.
Common diseases of arowana
Eyedrop
Feeding the bottom food for a long time will restore it if it is put back into the pond. Cover the fish tank with opaque black paper, put a white lamp on the top of the fish tank, feed the top food or put an object on the top of the fish tank to attract the attention of arowana, and remove the black paper after 3 months.
Gill inversion
Because the water quality is not clean, there is not enough space and dissolved oxygen, and the water temperature changes suddenly. At the early stage of the disease, you will see irregular movement of fish gills, shortness of breath, and the soft membrane on gills covers outward rather than inward, and you can see the red color of fish gills. Change the water quality as soon as possible and provide more oxygen, the fish gills will change from soft to hard, and there is no choice but to have surgery. Surgery needs: scissors, gloves, disinfectant alcohol, clean and moist cloth, anesthetic. Find a clean plastic bag, fill the bag with water, put arowana in the bag, and add anesthetic to the water in the bag. When the anesthetic works, take the arowana out of the bag, put it on a clean and moist cloth and trim it with scissors (ensure disinfection), then put the arowana back into the tank to increase dissolved oxygen. When arowana regains consciousness, let it rest and rest in dark conditions. If arowana is not interested in food, change 20%-30% water every day, change the water quality once every six days, increase the salt, and reduce the risk of parasite invasion.
white dot
Caused by parasitic protozoa, a certain part or most of the body of arowana is covered with white spots. It mainly affects the fins and reduces the appetite of arowana, and it is often seen that arowana rubs the body. Raise the temperature to 30 or even 34 degrees Celsius and add 3% salt. If it doesn't work, it will be treated separately in the medicine jar. The main symptom is that the diseased fish is covered with white spots all over the body, like spreading white powder, and in severe cases, it is like covering the fish with a milky white film. The cause of the disease is that cucurbitaceae plants are parasitic on fish. Main preventive measures: 1 spraying 0. 1 ~ 0.2 ppm mercurous nitrate in the whole pool; 2 Sprinkle 500ppm copper sulfate and 500ppm magnesium sulfate on the whole pool water.
prevent disease
Arowana has few diseases. As long as we pay attention to prevention, the success rate of culture is almost 100%. The methods are as follows: after the yinlong seedlings are taken out of the tank, each tank is disinfected with 2.4 million units of gentamicin sulfate to kill pathogenic bacteria, prevent the deterioration of water quality and prevent infection caused by transportation; In the process of feeding, only the right amount of antibiotics (oxytetracycline, tetracycline, etc. ) should be used for prevention every week.
Daily management of arowana
Change at least 20%-30% water every week, and the ammonia content shall not exceed 0. 1 ppm (mg/ 1). Don't let the temperature and pH suddenly change, if the change suddenly leads to sudden death of arowana. Check the PH value and other toxic substances every week to avoid countermeasures. Be careful when changing water to avoid the fear of arowana. Moreover, when raising arowana, you must avoid completely replacing it with new water, otherwise it will cause harm to the fish. If you see the fins and scales of arowana fall off, it is caused by too much water change. You can stop changing the water, and they will recover naturally. However, the amount of water exchanged should not be too small. Too little will make the fins opaque and the eyeballs turbid, leading to gills turning over.
filter
Young arowana is too big to be kept in a straw box. As big as a fish tank, the problem of filtration is more prominent. The filtration systems suitable for arowana culture mainly include upper filter, outer filter, upper+sand pumping filter and overflow filter. However, it should be noted that when arranging the arowana box, you should consider arranging a water pump (surf pump). This has great benefits: 1. It can form a powerful water flow; 2. It can increase dissolved oxygen in water; 3. More importantly, it can make arowana keep a certain amount of exercise to keep the graceful figure of the fish; 4. It is also important to avoid arowana turning over its gills, and trim the gills when it happens.