What kind of fish is this? From the fish pond in the community, please give some advice, thank you!

Seven-star swordfish is also known as bow-backed fish, seven-star flying swordfish, oriental swordfish and flower swordfish. Body length is 80 ~ 90 cm. The front half is wide, the tail is small and the back is slightly arched. Distributed in India, Myanmar and Thailand. Seven-star saury is gentle and likes to eat live small fish and shrimp.

Physical characteristics

The body is gray-black, with 3 ~ 10 black spots with white edges from beginning to end. The quantity is uncertain, seven-star saury.

Increase or decrease due to fish. There are no black spots on the body surface of young fish, but only 10 ~ 15 faint twill lines, which become black spots after adult fish.

Feeding characteristics

Mild temperament, nocturnal activity, can live with similar fish. The influent temperature is 22 ~ 28℃, and the water quality is weakly acidic. I like to eat live small fish and shrimp.

Reproductive characteristics

Artificial reproduction is more difficult. Seven star saury

After hiding in hidden objects such as rockeries during the day, I come out of eat small fish at night. Can be mixed with fish of similar size, and it is best to have rockeries, heavy trees or tall aquatic plants in the fish tank to hide. The water temperature is about 25 degrees, and the water quality is weakly acidic. You can buy a PH test paper and often measure the PH value of water, preferably between 6.5 and 7. Mixed fish farming should also like weak acid water quality.

Living habits

The origin of saury is India, Thailand, Myanmar and other countries. Appearance and habit: saury can reach 1 m in length, which is short and small among the aquarium. The fish's back is very high, gradually narrowing from the abdomen, buttocks to the tail, and extending backward to the tip of the caudal fin, which looks like a knife. The dorsal fin is short and transparent, and the gluteal fin extends from the abdomen to the tail and connects with the caudal fin, forming a slender edge with the same width, like a blade. The body is dark gray with oval black spots on both sides, hence the name Seven Star saury. Seven-star saury likes weak acid soft water, and has low requirements for water temperature. It can grow above 20℃, is a carnivorous fish and a delicious animal feed. Suitable for raising in large aquariums, it belongs to nocturnal fish, so it doesn't like swimming during the day and preys at night. Seven-star saury is an egg-laying fish, which is not easy to reproduce. Seven-star saury is a nocturnal fish, and generally likes to eat and feed at night, so pay more attention when feeding. Like dark places, you'd better put a place in the jar to hide it, so it's easier to adapt to the environment.

mixed culture

Seven star saury

In an aquarium, if there is a large group of seven-star fish swimming around in it, the pleasing sight will definitely fascinate you. However, the polyculture of saury is very particular! When choosing mixed fish, you can consider the following points: First, in * * *, there should not be much difference in the size of fish in a tank, and big fish will often bully small fish. Second, it is necessary to master the feeding habits of polyculture fish, and fish with different feeding habits will be ignored in a pool; Third, we should consider the adaptation of water quality and water temperature. Fourth, aggressive fish should not be mixed with gentle fish. On the contrary, mixed culture of aggressive fish can reduce mutual attacks. Finally, it should be emphasized that the spatial distribution of mixed culture saury should be uniform, and saury has strong territorial nature, so as to avoid territorial disputes due to high density. [ 1]

Aquaculture water

Seven star saury

(1) Activated carbon filter water: put activated carbon into a plastic or enamel bucket, and let tap water flow in from the bottom water inlet and out from the top water outlet. The filtered water is stored in an aquarium or other containers and can be used for daily feeding and reproduction of common tropical fish. (2) Filtering water with ion exchange resin: ion exchange resin is used as the filtering material, and calcium ion, magnesium ion and nitrite in water can be adsorbed by virtue of the adsorption capacity of anion exchange resin. (3) Deionized water: also known as distilled water. It is generally obtained by electrodialysis and electrolysis, and the water quality is very pure. Deionized water is very soft, and the oxygen content in the water is very low, so it is not suitable for feeding. It is often mixed with clean water to obtain water with different hardness and pH to meet the needs of different varieties of aquaculture water. (4) Rainwater: The water quality is soft and the content of metal ions is very small. Generally, it can be used in suburbs with fresh air, and can be used after being filtered in containers.

Feeding requirements

Seven star saury

Water temperature: 25-28℃ Hardness: 6-9dGH Ph: 6.5-6.8 Food: live bait for animals, small fish and shrimp Temperament: saury is a nocturnal fish and likes to swim and eat in dark light. Note: saury has tiny teeth in its mouth, so it is easy to swallow small fish. Don't mix small fish and raise seven-star knives. Life span: 8-65438.

Main points of purchase

The way to buy fish is to look, smell, ask and cut. Because the fish in the fish shop are "hundreds of fish", that is, different fish in each family fish tank with different water quality enter the fish tanks of retail stores in a short time, and these fish themselves have certain parasites and bacteria. If there is no good water, people in fish shops can only soak in the tank, so different water quality will excite these parasites and bacteria from the fish, and the sudden change of water quality will make the fish unable to adapt. The most obvious performance is that there are not many symptoms, but fish always die for no reason. People in fish shops will catch fish when they die. If you don't watch carefully, it's hard to see why the fish at home is worthless, but the price of retail stores has turned 7. Seven star saury

Why is it best to look, smell, ask and cut fish in a fish shop? First of all, to buy fish in a fish shop, we should not only look at the fish, but also look at the water in the tank and the filtration system. This is because the most important factors affecting the healthy growth of fish are water and filtration system. I can't see anything for a short time unless I don't walk, eat or drink for three days. So don't buy your favorite fish at a glance (unless it is extremely rare). It usually takes two to three weeks to buy fish in a store, and some take a month. Although it is very tiring and troublesome, the health rate of the fish bought in this way is above 90%, but it saves time and is convenient to get acquainted with the fish shop owner in the future. In this way, if the fish can live in their shop for two weeks to more than a month and the filtration system is good, it proves that the water in the fish shop is well raised and the fish are gradually adapted. At this time, people will say, what do you think of the filtration system and water quality? The first thing to look at is the clarity of water. For example, the transparency of water is good, but fish are hiding in some corners. This is because fish have a strong sense of urgency, which is mainly caused by discomfort to water quality and environment. The water is not very clear, but the fish is lively and greedy, which shows that the fish has completely adapted to the water quality and environment in the tank. It is also important whether there are a lot of fish droppings and residual bait in fish tanks and filter cotton. More feces is a good thing, which proves that the metabolism of fish is very good. If the fish in the tank is too clean, don't buy it. If there is residual bait in the tank, it proves that the fish's desire for food is not very strong (people in the fish shop will not increase the amount of food fed to the fish). Unless it is a straw vat, the normal water quality should be clear and transparent without color cast. If the water turns yellow, furan drugs may be being used to treat bacterial diseases; If the water is blue-green, methylene blue or malachite green can be used to treat diseases such as water mold and white hair. Some medicines, such as mercurous nitrate, are colorless but irritating, so if you want to smell the fish here, you should not only listen to the fish shop owner's introduction to the fish, but also smell the water in the jar with your nose, or dip your fingers in some water before drying it. Seven star saury

The best water quality has a faint fishy smell, and no or strong fishy smell proves that the ecosystem in the water has not been established or has collapsed. This can be of great help to you in choosing good fish. Asking is the simplest. In fact, it's time for you to examine the character, level and reputation of fish shop owners. Sometimes you may make a mistake on purpose, and see if he helps you correct it. Everyone has different views on this, so we won't discuss it much. Gee, do fish have veins, too Cutting here is not cutting the fish vein, but doing it, and it is also an important means for us to test the truth with practice. First, touch the cylinder wall of the bare cylinder or other equipment in the cylinder. If there is a little greasy feeling, it proves that the metabolism of fish is good, but it should definitely not be a lot of feelings. Too much is actually a manifestation of high nitrite content. Of course, you can take some water home and test it yourself. Touch the filter cotton by hand or look around the pump. If there is something like snot, it proves that the water quality is good and the nutrition is rich. You'd better bring a little PH test paper if it's convenient. After you buy it, just wash it with the method just introduced. Also, if you really want to buy fish, it is best not to choose holidays, which is also the time when fish shops sell more fish, that is, the dangerous period of fish, and the survival rate of repurchase is low.

Common diseases

Seven star saury

Anchor worm

(Anchored fish) (1) signs of infection. Female anchovies, they are parasites. When they stick to fish, they can be easily identified according to the appearance of their worms. In spring, when two oocysts of about 3 mm are formed at the free end of the body, their maximum length reaches about 20 mm. (2) A detailed description of the infection. Although anchovies have common names, they are not worms at all, but tiny crustaceans called copepods. Like most crustaceans, their maturity goes through several larval stages. The first larvae hatched from eggs swim freely in spring until they find a suitable host and attach themselves to gills. Once attached, they enter the non-swimming period. The males in the first hatched larvae fertilize the females and stop parasitizing. Then the mated males attach to the host fish and develop into worms. Females ovulate in spring, and then may die or continue to lay eggs several times. When the parasite dies, the holes left in the skin and muscles of the fish may cause secondary infection, so the fish cannot heal. (3), recommended treatment. After the anchor head worm goes deep into the fish tissue, it sticks itself firmly to the fish. People can select adult worms one by one, but it is a long process and potentially harmful to fish. Short-term immersion in 3% salt solution can also remove bugs from fish. Now there are aquarium treatments that can kill adults. Also in the pond, repeated use of anti-protozoan treatment agents will kill larvae. Using trichlorfon can also kill adults.

black spot

(Piju, also known as Stemona Piju, etc.) (1) signs of infection. Small black or brown spots, up to 2 mm wide, appear on the body and fins, and sometimes on the eyes and mouth. (2) A detailed description of the infection. Spots are cysts containing larvae of intestinal trematodes, such as Fasciola pidata, which contain heavy pigments. Larval stage is also called Fasciola pigmentosa. Adults live in the intestines of waterfowl and are disturbed by eating fish that hide larvae. In the viscera of waterfowl, the membrane wrapped around each larva is dispersed, and the worm matures after a few weeks. The eggs produced by adults are discharged from the excrement of birds, and the eggs that fall into the water develop into free-swimming larvae and parasitize on water snails. A few weeks later, the parasite leaves the water snail and begins another cycle of sending suitable fish hosts. When the parasite reaches the seven-star fish,

When it is about 1 mm wide, each insect produces a black film on its body and forms unique spots under its skin. The slight infection of black spot disease does not harm fish, because the life cycle and environmental conditions are complex, and it will not spread black spot disease from one fish to another. (3), recommended treatment. New antiparasitic agents can kill parasites, but once black spots are formed, they will leave traces. The most effective preventive measure is to break the growth cycle of parasites and ensure that waterfowl are not near ponds or aquariums, and no parasitic snails appear.

sleeping sickness

Trichinella spiralis-sleeping sickness (Cryptosporidium, now including trypanosomiasis and trypanosomiasis) (1), signs of infection. The fish infected with cryptosporidium is listless, swimming abnormally, the fish becomes emaciated, the eye socket is sunken, and the gills are white (indicating the lack of red blood cells). The badly damaged fish died. Trypanosoma seems to be relatively non-pathogenic and will not produce such serious symptoms. (2) A detailed description of the infection. Cryptosporidium and Trypanosoma are unicellular organisms (protozoa) with velvety flagella, so they are called "flagellates". They live in the blood as parasites. Harmful cryptoflagellates have two flagella, while completely harmless trypanosoma has only one flagella. To see this parasite on a blood smear, you need a 300 times microscope. Both parasites are transmitted by leeches, the second host. Flagellates live harmlessly in the intestines of leeches, which can infect fish when they bite. (3) Recommended treatment methods. No chemical treatment agent has been found that can effectively prevent and control haemoflagellates in ornamental fish. Since only the fish attacked by leeches will be infected, it is only necessary to take out the infected fish and get rid of the leeches. But it is quite easy to do this in an aquarium, and it is much more difficult to solve this problem in an infected pond.

Inclined tube worm

(1) signs of infection. The infringed fish rubbed hard objects and closed their fins. The skin is covered with light blue transparent body, especially between Guan and dorsal fin. If the gills are damaged, the respiratory rate is obviously accelerated. In the late stage of infection, the skin surface swells and then falls off. (2) A detailed description of the infection. Oblique tube worms are ciliates, single-celled saury with seven stars.

Creatures that can only be seen with a microscope are covered with uneven fluff, which pushes worms forward in the water. Trichinella spiralis can be seen with a medium power microscope, but the samples must be collected quickly, because Trichinella spiralis leaves the fish within two hours after death. This parasite attacks injured fish first, but spreads to healthy fish under crowded environmental conditions. Trichinella makes fish very weak, and in severe cases, it will cause long-term damage to gills. Trichinella spiralis reproduces by cell division. (3), recommended treatment. If the fish are strong, the best way to treat freshwater fish is to soak them in 3% salt water, let them stay inside until they curl up, and then quickly put them back in their aquarium. As an alternative and less irritating treatment method, the fish should be put into 1% salt water 10- 15 minutes, and then the fish should be put back into clear water. The best temperature for treating tropical fish is 28-30 degrees. Or a new antiparasitic therapeutic agent can be used. If the parasite stays in an aquarium with no fish and a temperature of 30 degrees for about 5 days, it will die. But parasites on fish must also be treated.

A crack in the cloud

(1) signs of infection. One or both eyes of the fish are covered with clouds and appear white. Fish may show signs of nervousness, their colors are abnormal, or they behave like normal fish. (2) A detailed description of the infection. There are many reasons for cloud eyes. Such as Chlamydomonas and cryptosporidiosis, and tuberculosis symptoms of fish. But non-special bacterial infection is often the cause of cloud eye. (3), recommended treatment. Determine the possible causes of the problem and treat it as soon as possible to prevent it from causing harm to the nervous system. If it is a parasitic infection (such as Chlamydomonas), use the corresponding treatment. If the root cause of the disease is bacteria, then therapeutic agents containing antibacterial complexes such as phenoxyethanol or furans are used for treatment. Keeping a good environment, especially using clean water, can minimize the occurrence of cloud eyes, because dirty water may be a trigger, so adding a small amount of salt to water can help prevent it.

Hydromycetes

Fish mycosis-water mold (water mold and cotton mold) (1), signs of infection. The obvious sign of infection is cotton-wool vegetation, usually white, but sometimes gray-black to green. Fungi usually originate from tree trunks, but may also originate from damaged parts. It can spread and damage fins, mouth, eyes and gills. (2) A detailed description of the infection. Fungi are plants that grow on dead organic matter. A typical fungal body or mycelium consists of very fine filaments or exobacteria, which penetrate dead or decaying tissues and directly absorb nutrients through the cell wall. Therefore, although fungal spores appear in the water, healthy fish can resist infection. Spores are released from the swollen tips of some exophytes and swim freely with two flagella until they stay in suitable tissues and start to grow into another fungal mass. Fungi only attack injured fish, or fish that are weak in some ways. If the invasion seems to occur spontaneously, it may be a secondary infection of tissues damaged by other reasons, such as skin trematodes. In these cases, both the fungus and the initial infection need treatment, and if not treated, the fungus will die. Damaged or unfertilized eggs are particularly vulnerable to fungal attacks, while healthy eggs in the same group can hatch normally. It is usually wise to transfer eggs with fungal vegetation to protect healthy eggs from inhibition during development. Seven star saury

(3), recommended treatment. In the aquarium, possible infection can be prevented by checking whether the water is in good condition, whether the water temperature is appropriate, and whether the water is too alkaline (PH7.2 is the best in the freshwater aquarium). Many therapeutic agents are recommended, but some of them have serious shortcomings. Salt water bath is a traditional treatment for freshwater fish diseases, but it will cause inappropriate irritation and need to be replaced frequently, and it is not particularly effective when used alone. Methylene blue is effective for mild cases, but the prescribed dose will stain the water, making it difficult to continuously check the development of the disease. You can paint malachite green on the infected area. There are several new special treatment agents, which are usually effective for fungi. In ponds, fungi usually appear in spring, when fish are weakest or damaged after spawning. Before the wet or cold weather begins, feed balanced nutrition bait to fatten the fish and ensure the PH value of the water is between 6.5 and 7.8, which may reduce the chance of fungal infection. There is a special fungus treatment agent in the pond. However, according to the environmental conditions, it is best to transfer the infected fish to a suitable container that can maintain a relatively stable state for treatment; The disparity between cold and heat will reduce the therapeutic effect of drugs and promote further infection. For example, when taking an old-fashioned bath, you must carefully transfer the fish to a large container filled with dechlorinated water or aged water. Ideally, water should be oxygenated. Avoid unnecessary stimulation to fish at all costs. When transferring fish, use absorbent cotton to wipe off the fungal vegetation on the fish.