What if there are a lot of algae in the fish pond? No, it's a trick.

Algae are low-grade plants, widely live in water and soil, the right amount of algae in the water has a conservation effect on ornamental fish, and many algae are rich in nutrition. it can become an auxiliary food for tropical fish, especially juvenile fish and algae-loving Marys, all kinds of squirrel fish and other fish. However, excessive algae can adhere to the leaves of aquatic plants, water tank walls and filtration equipment, which seriously affect the photosynthesis of aquatic plants. If not removed in time, the environment in the water tank will deteriorate and threaten the survival of ornamental fish. In addition, some algae multiply in large numbers in ponds, which can corrupt the water quality and produce toxic substances, resulting in the occurrence of fish disease.

Today we will list several kinds of algae that often occur in fish ponds and their control measures.

1. Diatoms

Diatom is a kind of important plankton with wide distribution, many species and large quantity, so it is called the "grassland" of the ocean. They are the main primary producers of water bodies and the natural bait for filter-feeding fish. But they can also make the walls of the fish tank and the coral sand, quartz sand and reefs in the tank slowly darken until they turn brown, affecting the ornamental effect. Therefore, it is necessary to control the appropriate number of diatoms in culture water.

Diatoms (Diatom), also known as mushy algae, belong to the diatom phylum, there are about 300 genera, more than 11200 species, the size of 3.5 to 4 mm, generally 20 to 30 Hui meters of diatoms are the most common. Diatoms are a kind of single-celled plants with pigments, which are often connected by several or many individual cells into filaments and various groups. The nucleus is 1, often located in the center of the cell; the vegetative body has no flagellum, the sperm has flagellum type, and the diatom is of various forms, including round, polygonal, spindle, S-shaped, crescent-shaped and bow-shaped. It can grow in fresh water, sea water, moist surface, rocks, plants and tank walls, and glide on the solid surface. According to the life style of diatoms, it can be divided into benthic diatoms and planktonic diatoms. Benthic diatoms are common in aquariums, such as Navicuta sp., Navicuta latissima Gregory, Amphora sp., Cocconeis sp. And Achnanthes Orientalis Hustedt and so on. Diatoms mainly divide and reproduce. In nature, diatoms reproduce very fast. Some species can reproduce twice every four hours or so, and even produce hundreds of millions of offspring within a few days. This also happens in fish tanks with suitable conditions.

The main reasons for the occurrence of diatoms in ornamental fish culture water are:

1. When setting up the tank, the sand at the bottom of the aquarium is not washed, which is the main cause of the occurrence of sand algae, especially when the tank is set up in winter.

2. At the initial stage of setting up the cylinder, the filtration system is not perfect, and the beneficial microorganisms can not grow and reproduce normally.

3. The nitrate in water is too high.

4. The decomposition of organic matter in water is incomplete.

5. Light factor. The light intensity of 2000-3000 lux is the most suitable for benthic diatom growth, which is equivalent to a 40-watt fluorescent lamp, which is the normal light intensity in a fish tank, so diatoms are easy to appear in fish tanks. It is usually difficult for diatoms to reproduce below 3 ℃, while aquatic plants and coral reef organisms generally live in tropical and subtropical regions, and the diatoms brought by them are most likely to reproduce at 24-27 ℃, which is why diatoms are easy to reproduce in aquariums in summer.

Prevention and cure measures

It is an effective way to control algae by using fish, snails or shrimp that feed on algae. For example, beard heteromorphism and whiplash are the most effective ideal species for swallowing diatoms.

Second, green moss

Moss is the general name of filamentous green algae, commonly known as "raising placenta", including sponges, double-star algae and plankton. Moss likes to grow in the shallow water with high transparency in fish ponds, and begins to grow under suitable ecological conditions (the water temperature is about 20 ℃). In the early stage, it grows into strands of dark green filaments that look like hair attached to the bottom of the water, with sticky hands; it gradually propagates, such as reticulated suspension in the water; after aging, it becomes cotton floc, floating on the water, showing a yellowish green color. It occurs all over the country, and the occurrence period is mostly from May to September.

Harm

During the mass reproduction of moss, the inorganic salts in the water are seriously consumed, the metabolism of normal nutrients in the pond water is destroyed, the water quality becomes thin, and the plankton needed for fish fry can not reproduce in large quantities, affecting the feeding and activities of ornamental fish, thus affecting their growth and reducing the survival rate. At the same time, a large number of algae and moss are attached to the body surface of ornamental fish, affecting their growth and commercial value. when fry or small fish are drilled into the moss, they are often entangled by disorderly filaments and cannot swim out, resulting in their death and decomposition in the pond. produce toxic substances such as hydrogen sulfide and hydroxylamine, increase the content of ammonia nitrogen in the pond and reduce the dissolved oxygen in the water, resulting in anoxic poisoning of ornamental fish.

Governance measures

1. Prevention

1) thorough cleaning of the pool with quicklime can kill moss. After cleaning the pool, keep the pool water at a depth of more than 1 meter, so that moss can not reproduce in large quantities.

2) thoroughly disinfect the fish pond before receiving water, make the water body yellowish green in time, and the transparency is controlled at 25cm to 35cm, so that the bait organisms can reproduce as soon as possible, so as to control the growth of moss.

3) when releasing fish fry in the low water temperature season, it is not appropriate to plant aquatic plants as shade immediately to prevent them from being brought into moss.

4) change the water in time to avoid excessive content of organic matter in the water.

5) cover the moss with 75 grams of plant ash per cubic meter of water before releasing fish fry, so that it can not get sunlight and photosynthesis, and a large number of people die.

2. Treatment

1) when moss is multiplied in large quantities, the moss at the bottom of the pond can be fished out in the afternoon on a sunny day, and then 75 grams of organic fertilizer is applied according to the fat and thin of the pond water.

2) the whole pool is sprinkled with copper sulfate at the concentration of 0.71g per cubic meter, focusing on the dense distribution of moss, and the moss can be effectively killed by stirring the moss with tools at the same time. Change the water after 2 days, so as not to cause the moss to decompose and produce other harmful gases to worsen the water quality.

3) according to 80 grams of raw gypsum powder per cubic meter of water, evenly sprinkle the whole pond after feeding the fish in the afternoon for 3 times, and then pour water 10-20 cm, each time at an interval of 3-4 days, if the moss is serious, the dosage can be increased to 100 grams; this method generally will not make the water thinner, nor will it cause hypoxia, so the killing effect is more significant.

4) sprinkle quicklime at the place where the algae gather, 100g to 150g per square meter, and kill the moss by suddenly changing the pH of the local water body.

5) using a new type of water quality improver, Daozajing (developed by Shanghai Zhongyu Science and Technology Research Institute), 0.75 grams per cubic meter of water can be killed at once.

6) if the effect of traditional methods such as copper sulfate whole pool sprinkling method and plant ash covering method is not satisfactory, bleach point killing method can be used, that is, bleaching powder (effective chlorine content 30%) is diluted with water on a windless day in the morning, and the moss is poured one by one at the top of the moss. If there is a "moss" that leaks the net, it is irrigated again the next day, using the strong lethal power of bleach to make the mud moss degenerate and whiten, and finally die, and the effect is very good.

Matters needing attention in diagnosis and treatment

When using drugs to kill algae, you should choose continuous sunny weather and do it in the morning, and turn on the aerator in time after using the medicine. It is better to sprinkle 4.5 × 7.5 grams of photosynthetic bacteria and other biological agents per cubic meter while killing algae.

Third, water net algae

Water net algae is commonly known as green filamentous algae, which belongs to the family of water net algae. The algal body consists of many long cylindrical cells connected to each other to form a reticular body, and each "mesh" is made up of 5 to 6 cells. Because it gathers like a net bag, it is called water net algae. The algae likes to grow in fertilizer and water rich in organic matter, which usually occurs in spring.

Harm

Similar to moss.

Prevention and cure measures

It's the same as moss.

4. Tripterygium

Chrysophyta, also known as soil algae, belongs to Chrysophyta, Trihaeaceae, is a cold-water unicellular algae, the algae is oval, long oval or spherical, easy to deform, the size is 6-15 mm × 5-13.5 mm, and there are 3 flagella at the front end of the cell. there are two yellowish green pigments in the body. It can occur in all seasons of the year, mainly in spring, autumn and winter, so the water temperature is low, other algae are affected by low temperature, reproduce slowly and the number is small, while Tripterygium can tolerate low temperature and become the dominant species, causing harm. It generally occurs less in summer, because of the high water temperature in summer, cyanobacteria, green algae and other algae multiply in large quantities, thus inhibiting the development of small trichaeophyta, but when the water quality condition is suitable for the reproduction of small trichaeophyta, especially when the total ammonia content is low, cyanobacteria and green algae can not become worried species, the harm of small trichaochloa can still occur. Tripterygium is mainly popular in the ponds of saline-alkali zones in the north of China. Strips, ponds, reservoirs, ornamental fish, farmed fish, wild miscellaneous fish and aquatic animals breathing through gills can be affected.

Symptoms and harm

Trihaeophyta can produce many kinds of toxins, such as fish toxin, cytotoxin, neurotoxin and hemolytic toxin, which can cause fish poisoning. In the early stage of the disease, when the toxicity in the water is small, most of the ornamental fish begin to show restless vegetarian salt body in the morning to accelerate the frequency of direct respiration, swim rapidly, the direction is uncertain, and soon tend to calm down. Gradually slow down, the fish began to concentrate to the shallow corner of the pond, a few fish motionless, arranged irregularly, disturbed, that is, swim to the deep water, and soon return. The fish secrete a lot of mucus, the base of the pectoral fin is congested obviously, the base of each fin is gradually congested, the color of the back of the fish becomes lighter, the response is more slow and calm, and the respiratory rate decreases gradually. With the extension of poisoning time, the fish body paralysis, rigor, caudal fin, dorsal fin and ventral fin can not swing after the pectoral fin, only the pectoral fin can still swing, but can not move forward, there is no response to the touch, Gill cover, orbit, jaw, body surface congestion, erythema of different sizes, some even into pieces. Fish are covered in the four corners and shallow waters of the pond, usually facing the shore, neatly arranged, motionless under the surface of the water, but not floating head, disturbed and unresponsive, when breathing is extremely weak, 22 or less per minute. Intermittent struggling breathing occurs before dying, soon losing balance and dying, but some fish remain in their natural state after death.

Main points of diagnosis

1. On-the-spot diagnosis can be made according to the time of onset, epidemiological characteristics and symptoms.

2. Laboratory diagnosis when the density of trichaeophyta in the water is more than 30 million per liter, the water is yellowish brown, which can cause the death of ornamental fish, so a microscope should be used to calculate its number in laboratory diagnosis. at the same time, check the gills and internal organs of diseased fish for symptoms of infectious diseases and parasites.

Prevention and cure measures

1. Preventive measures

The main results are as follows: 1) keeping the proper fertility of pond water in winter and early spring is the best way to prevent the poisoning of trematophyta, because the water quality is beneficial to the reproduction of algae faster than that of fertilizer, which can effectively restrain the nutrition of trematophyta and avoid its harm.

2) when the content of total ammonia in the water is more than 0.25 g / m, Trihaeophyta can not become the dominant species in the fish pond, so when the transparency of the water is high, ammonium fertilizer, urea, nitrogen water, nitrogen and phosphorus compound fertilizer and organic fertilizer can be applied regularly to the pond to stabilize the total ammonia in 0.25 g / m water, which can play an effective preventive role.

2. The following treatments can be taken for the occurrence of toxicosis caused by Trichoderma.

The main results are as follows: 1) for the ornamental fish that have just appeared the poisoning symptoms of small and Trihaeophyta, they can be transferred to the fish ponds with fatter water quality or injected with new water, which can effectively relieve the poisoning symptoms.

2) the whole pool was sprinkled with copper sulfate at a concentration of 0.7 grams per cubic meter, and 0.3% clay mud water was sprinkled throughout the pool the next day. Using the polarity of clay particles to absorb toxins, the poisoning symptoms of fish can be greatly alleviated and returned to normal within 12 hours. However, copper sulfate can only inhibit the secretion of toxins from Tripterygium, or weaken the activity of fish toxins, but it can not kill it. When the efficacy is weakened, it can occur again under certain conditions.

3) when a large number of trichaeophyta is found in the water, ammonium salts containing about 20% ammonia (such as ammonium sulfate, ammonium chloride, ammonium bicarbonate) can be sprinkled all over the pond, 20 grams per cubic meter of water, or 12 grams of urea per cubic meter of water, so that the ammonium ion in the water reaches 0.06 to 0.1 grams per cubic meter, which can make the algae expand and disintegrate until all die. However, fry and fry that are sensitive to ammonia should be used with caution.

Matters needing attention in diagnosis and treatment-differential diagnosis

Note the difference from pan-pooling. The poisoning of Trihaeophyta does not show the phenomenon of floating head, but is motionless under the water surface, and the content of dissolved oxygen in the water is high, and there are a large number of trichaeophyllum in the water. The fin base, Gill cover and orbit of the poisoned fish are congested.

That's all for today. If the above algae occur in the aquarium, please learn from them. I hope you can help your fish friends. If there are any inadequacies, I hope you can give us your advice.