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Almost every aquarist, even a beginner, who knows very little about acquired fish, is thinking about breeding. At the same time, he is guided by recommendations derived from literature sources, advice from acquaintances or fish marketers on the market. But as soon as the aquarium, inanimate with recommendations, starts to embody them in practice, the first attempts are soon convinced of the futility. And what's strange, everything is done, it seems, as it should, but ... And then the suspicion that experienced aquarists do not negotiate something, keep key secrets for fear of competition. Yes, there are indeed secrets, but they belong to the category of those who are "all over the world." And no one is going to hide them, they are published. In articles and books everything is written about, only we do not know how to read them. We will open any book describing aquarium fishes, and we will find such data: the Russian and Latin name of the fish with the indication of the species and genus, its homeland, the name of the reservoir in which it is distributed in nature, the size of the male and female, their sex differences, etc. As a rule, we skip the first information and hurry to learn the main thing - in what conditions, to contain fish. But in vain ...

The question of the geography of the distribution of the species that lives in the aquarium and which it is decided to plant is far from idle. If the homeland is specified and, moreover, if a specific reservoir, river, inflow is indicated, it is necessary to clarify the fidelity and completeness of this information by all possible sources, then to try to imagine with maps of relief, geological, soil, climatic, how, under what conditions The life of fish at all stages of its development, comparing recommendations received from books and from friends with their conclusions. Much, of course, will be confirmed, but a lot of advice will cause disagreement, so they will be logically absurd. In any case, observing the behavior of fish in common and spawning aquariums, analyzing the failures or results of small victories, one can rely on their judgments on knowledge of their nature. Do not forget about the importance of such information as the physical properties of the environment, plant and animal life on the banks and directly in the pond, the speed of the current, the influence of tides and tides. All these factors should be considered interrelated and in the dynamics of time and seasonality.

Such knowledge will help with other eyes to look at the habitual inhabitants of the indoor pool. They are one of the main keys to understanding what the secret of breeding is. The second key is in knowledge of the place assigned to the species of interest by biological science in the general system of fish. According to this harmonious system, animals are grouped according to related similar features. The place of fish in the system is indicated in the scientific name (although it is written in Latin, but it is not difficult to learn). The name of the fish consists of two words denoting the name of the species (the second word) and the genus to which this species is referred (the first word). But in all publications it is easy to find information on which family includes the genus. The description of the biology of fish of one family is given, as a rule, in more detail, as well as a description of the characteristics of the content and breeding of the genus. When describing the species, it is often noted that the breeding is similar to breeding of the family or genus. And it is really very similar sometimes so that if, for example, the details of breeding of Sumatran barbs are known, then it is enough to know only some characteristic insignificant details for the breeding of fire barbs. If the breeding of macro-subpopulations was successful, breeding of males should not be difficult.

However, there are springs, or factors that influence the breeding mechanism, which make it necessary to take into account the features of not only the species, but also each individual. We are dealing with living beings. Not all fish and not in any time suitable for us can give offspring. It is in the fish themselves, their physical development, their health, their readiness, and their "desire" to participate in spawning at the moment, behavioral features (for example, increased aggressiveness of some or inadmissible passivity of others), and not in water hardness and pH All the key to unraveling the failures. Only from healthy, well-developed, not oppressed by poor conditions of maintenance and monotonous feeding, reached the sexual maturity of fish, one can wait for offspring. Not understanding this, many aquarists start by planting the first pair of producers (especially those with a belly that seems to be full of caviar) to spawn, and, in accordance with all the rules prescribed by recommendations, try to obtain from them offspring. Of course, there are also good luck, but they should not be seen as a rule, but as an exception.

So, let's clarify the key positions of the approach to successful breeding:

The need to constantly increase the level of biological knowledge of the fish farmer or the presence of natural talent, observation and sensitivity to the requirements of a living organism (which, unfortunately, does not always help in the absence of knowledge);

The ability to creatively relate to advice and recommendations, refining and supplementing them with personal conclusions on the basis of studying by all possible sources of living conditions of a bred species in natural, natural conditions, as well as a family of features of breeding biology common to the whole genus;

The willingness to abandon their personal "I want today!" If the fish are not ready and physically ready for production of offspring, and to work patiently, selecting future growers, preparing them for spawning. There should not be any violence.

And I would also like to advise a beginner fish farmer not to complicate matters with his unconscious actions, having read and listened to various recipes for breeding. Very often fish spawn directly in a common aquarium, if they are there well, and often without the knowledge of the lover. Do only what is not in doubt is necessary. Do not disturb your pets. Watch them carefully. Be sure to keep records, not trusting the memory. These observations will help to understand their behavior and adjust their actions. Count on a shortcut to success should never be. It is best to set yourself up for a full program, and it, as practice confirms, consists of the following stages:

Preparation of the spawning farm in accordance with the requirements of the species (spawning in a common aquarium is not always possible to bring to an end);

Cultivation and selection of future producers (this stage is the longest and can last sometimes up to a year, depending on the type with which the work is done);

Preparation and selection of producers for spawning;

Stimulation of spawning;

Spawning;

Preservation of eggs and larvae in the early stages of development;

Preservation and feeding of larvae and fry at an early stage of development.

Only after the fry gets stronger, they will be transferred to spacious outgrowth tanks, their confident feeding will be adjusted, it will be possible to consider that all difficulties of breeding have been overcome. The features of each stage of fish breeding in an aquarium are specific and depend on the type of fish, and the boundaries separating one stage from another are sometimes blurred. Complications may occur at each of these stages, and the process will be interrupted. Can all these steps go without the participation of an aquarist? Yes, it happens, if the aquarium has all the necessary conditions, and this is the merit of the aquarist. But if there are such conditions, can we assume that the aquarist has nothing to do with it? On the contrary, it will be an aquarist an unexpected gift from the fish in gratitude for his care.

Preparation of aquariums for spawning.

From the point of view of science, reproduction is a link in the life cycle that, in conjunction with other links, ensures the reproduction of the population and the preservation of the species. Methods of spawning are associated with the adaptation of fish to certain conditions of reproduction and development of young fish, with a way of life of fish and reflect the main ecological moments of the embryonic period and the main features of all other periods of life. In many ways, the way and place of egg laying by producers is predetermined by the oxygen conditions for the development of their offspring. In the course of evolution, adaptations to laying eggs under the water were developed. In many cases, getting into the water, the caviar becomes sticky and develops, having attached to this or that substratum. In the aquarium, we are obliged to model the conditions corresponding to natural conditions.

For most fish, fertilization and the development of eggs outside the mother's body are characteristic. Moreover, fish choose a place for laying eggs, which provides the necessary conditions for its protection and development. Some fish lay eggs among aquatic plants (phytophils), others on stones (lithophils) or on sand (psammophiles). There are fish preferring for calf silt (pelophiles), there are - building nests from air bubbles (afrophiles) or from plants. A fish gorchaki, for example, have adapted to lay eggs in the mantle cavity of mollusks of perlovits, bezubok (ostracophils). Fish of some species, preferring spawning on the current, have caviar, the development of which occurs in the water column (pelagophils). Reducing the protection of caviar is compensated by a large number of eggs. Fish that do not care about their offspring, spawning on the current or spreading eggs among the plants, are the most prolific; Laying eggs on stones, in nests, shelters and guarding it - less prolific. The lowest fecundity is found in fish that carry eggs in the mouth or in the brood chamber on the body (this is how the needle fish does), as well as viviparous. A typical example of the ability of a species to adapt to preserve the offspring to the most unusual conditions is the spawning of spawning carpubs (notobranchies, roloffy, cynolebias, pterolebias, astrophonduloses) that live in savannah conditions, where the climate is characterized by alternating periods of rains and prolonged droughts with complete drying of water in temporary reservoirs . For a short period of life they manage not only to turn themselves out of eggs, but also to grow up to sexual maturity to apply technical means of protecting eggs and fry from the producers themselves. Given the low water flow in the home ponds, for some fish (catfish-somersault, synodontis, ancistrus), flow is created by means of pumps, pumps, injectors.

In our aquariums there are fish that lay eggs in almost all the ways listed. Items on which fish are laying eggs, and also plants are called substrates. When preparing spawning tanks or arranging a convenient spawning area in a common aquarium, the substrate should be positioned so that the fish can comfortably use it and there are no external disturbances and irritants distracting them so that there are reliable shelters nearby. In some cases, you do not need spawning) are planted in a rider. It is better to make it yourself (being sold in stores are small and of little use) from mesh material on the frame and hanging on the wall of the aquarium or making it floating. The fry born will be able to escape through the holes of the grid of the rider to the aquarium, in which, of course, there should be no fish eating fry. In small aquariums use an inclined or vertically mounted grate, which fences the vessel into two parts. In any case, fry should be able to get to the water surface from the first minutes of birth.

As a rule, fish that do not care about their offspring do not see their eggs, it blows away with a current of water or hides dense vegetation. But in the aquarium these fish, when they see the roe, greedily attack it and eat it. To protect eggs, a grid is used, which is suitable for separator mesh, any other plastic mesh or lattice is rigid or flexible, but stretched to a rigid frame. The grid is set so that there are no gaps along the perimeter through which the fish could penetrate, and there would be 3-4 cm between the bottom and the grid. A flexible elastic grid can be laid with a bend.

Caviar of some fish species is so sticky that it can be carried along with the substrate in another incubation vessel. Very often plants are replaced with an artificial substrate. Basically, these are nylon threads (sponges), which are distinguished from plants by the advantage that they can be boiled for disinfection purposes. For fish having sticky eggs or eggs with sticky fibers, the substrate must be small-leaved plants, unpretentious, in many cases adapted to life in soft water with a weakly acidic and acidic reaction (necessary during spawning), and also not demanding of light (Spawning aquariums often obscure). For such purposes, ferns are suitable (especially good Thai), as well as mosses (for example, Javanese), although for fish with a short spawning period and those who prefer bright lighting can be used bundled or basted as a substrate should be treated with caution. It is desirable to choose unpainted yarns or to check (by boiling), whether they emit coloring or other water-spoiling substances. In addition, do not take sponges with thin threads, in which the fish can get confused and die. Fish are also entangled in grids (like grids for packing vegetables).

There are fish jumping out of the water to lay eggs on the underside of the plant surface sheet. Such spawning is characteristic of haracin fishes, Arnold's Copernicus. In the conditions of the fish aquarium, a cover glass is arranged. If there is no such glass, the fish will lay the eggs on the aquarium wall, but above the water level.

Some fish prefer to lay eggs in cavities of objects, cracks, caves. In the aquarium with such fish are placed ceramic (used as meliorators for drainage) and plastic tubes, flower pots. In the latter, the bottom opening is widened, the part of the side wall is chipped off, the pots are placed upside down or put on their side so that the fish can conveniently dive into one hole and come out, if necessary, from the other.

For discus, high ceramic cones (pot-tomb) are made on special orders, on the protrusions of which caviar and larvae are more easily retained. For spawning carpubs, diving caviar laying in the ground (cynolebias, pterolebias, astrofundulas), a "birdhouse" is built-deep, closed boxes on top with peat baked peanuts on the bottom and a hole in the top of the side wall (5-6 cm in diameter). These "birdhouses" are placed at the bottom of the spawning aquarium, and the fish find a hole, climb inside, where they lay their eggs.

For the production of substrates, a wide variety of materials are used: ceramics (hollow bricks, roofing tiles), articles made of Plexiglas and other plastics, coconut shells, glass and floating polystyrene beads. However, all substrates should have one property - not to release toxic substances into the water.

Among cichlids there are fish phytophiles, laying eggs on leaves of plants, for example, scaly. They prefer inclined planes located at an average depth from the surface of the water. Scalamas are not always given the opportunity to leave offspring, they take away their eggs about two hours after spawning and are transferred together with the substrate into a separate vessel. Leaves in this case (in order not to spoil the plants) are replaced by plastic or on plates fixed under the water at an angle. Scalarians quickly get used to such a replacement and subsequently willingly lay eggs on an artificial substrate. The scalars, in which the eggs are not taken away, transfer the larvae that have disappeared to another leaf and, if they have not lost their parental instinct, continue to look after them.

Some cichlids incubate eggs in the mouth. Eggs laid in a hole dug in the sand, the male fertilizes, after which the female takes caviar in her mouth. So haplohromisy, trophies, laboteotropes, melanochromises, pseudotrofeices and other species are bred.

For some fish laying eggs in the ground (silt, sand) - basically these are roasted karzubes - as a substrate requires boiled peat crumb or well washed medium-grained sand, another (non-annual carp-toothed) - can be offered as a substrate of plants, which then together with Very sticky eggs are transferred to a separate incubation vessel.

Eggs in foam nests, floating on the surface, are laid off by popular, well-known aquarists labyrinthine fish (males, lalii, macropods, gouramis, etc.). But there are fish that build foam lodes under wide leaves closer to the surface of the water. Such, for example, include catfish of the genus Hoplosterum and Dianema, who choose a place for building a foam nest under a wide floating leaf.

The spawning aquarium must be covered with a cover slip. This will not only prevent the ingress of dust, but will also reduce the losses of valuable producers, which often jump to the floor during spawning.

Cultivation and selection of producers.

It can be stated with all certainty that the correct, well-timed preparation of future producers and the successful selection of couples solve many problems.

Experienced aquarists begin to select fish and prepare them as future producers long before they reach puberty. So, the Sumatran barbs, whose puberty comes at the age of about 8 months, to prepare as producers begin with a 4-month-old age. For this purpose, not a pair, but 9, 13 or more strong young fish is selected. Considering that males and females in many species at an early age do not have pronounced sex differences, but can further differ in size (females are larger than males and vice versa), not only the largest but also the average fatness is selected, and not very large, But healthy, normally developing, sufficiently active. Of course, the greater the choice, the more guarantees of success in selecting a pair in the future. In general, experienced aquarists try to acquire a group of fish at an early age and grow them independently, to the sexually mature age.

Fish of some species, even adults, have very weakly expressed secondary sexual characteristics, and it is possible to distinguish the male from the female only during the spawning period (or on the eve), according to the behavior or the changes that appear on the eve of reproduction. Such species include, for example, the scalar, goldfish, astronotus, and others.

The formation of future producers is affected by deviations from the recommended conditions of maintenance and feeding. The fact is that to the fish left for simple maintenance, and the fish selected for repair, a different approach is required. For example, if we hold goldfish for a long time in a round aquarium with a capacity of up to 20 liters, they will be cramped, but with regular water substitution, aeration, filtration, suction of pollutants, they will live. They will not only grow, as they are supposed to. A year and even two to put such fish to spawn is useless. A similar example can be given both with the scalars, and with the thrones, and with the barbs, and even with the guppies. Thus, the stunted fish, which aquarists call "tightened", grown up in a close aquarium, can not be good growers, and in some cases from long fish can not even wait for offspring.

The conclusion is as follows: selected as future producers of fish should be kept in spacious aquariums with a sparse planting and, if possible, separately from all other fish. In pond fisheries, there are even special repair, summer-uterine, winter-matt ponds, where each producer is kept in special account for several years, fed and nursed. Has its own characteristics and feeding regime of future producers. From an early age they should be given full-fledged, balanced by the presence of components that meet the requirements of this type of food, paying attention to the norm, not allowing regular overfeeding. If the first and second requirements are not respected simultaneously and constantly, the result can be infertility.

As is known, aquarium fishes originate from warm tropical and subtropical reservoirs, hence, their requirements to the temperature regime are special. In recent years, heating systems have been increasingly used, and on average the water in the aquariums is maintained at a much higher temperature level than it was thirty years ago. This can be seen by comparing old and current recommendations. If earlier everyone knew that the room temperature of water (20-22 ° C) suits many types of fish, now there are recommendations to contain guppies at a temperature of 25-26 ° C, the same applies to goldfish (short-hair, veil). Are such recommendations good or not for growing future producers? In any case, the advice to keep fish of tropical ponds at a temperature of at least 24 ° C is justified.

Scalas, cockerels, barbs, many other types of aquarium fish feel better and are less likely to get sick, living in warm water. And yet, a constant content at elevated temperatures leads to increased development and premature aging, that is, shortens life expectancy. It should be remembered that high temperatures are not constant in the homeland of fish, and the increase in temperature for many species is associated with the emergence and rapid development of food objects, increased sexual activity, maturation of sexual products, which serves as a stimulation for reproduction, which we will discuss below. Taking into account the above, experienced aquarists recommend keeping fishes intended for spawning from an early age on the lower threshold of the temperature regime. This recommendation applies to barbs, blue neon, viviparous fish and many others, although not at all. Moreover, practice has shown that the content of some time producers (especially males) at low temperatures (of course, within the acceptable limits) subsequently increases their sexual activity. Thus, it is necessary to prepare future producers in healthy "spartan" conditions, without inhibiting or weakening them, without hampering their development, but without making them sissy, obese, incapable of giving offspring, individuals.

Sexual maturity occurs in fish at different ages. For example, in spawning karpozubyh in 3-4 weeks, in astronotus, goldfish - in two years. This is due to various natural conditions, as well as the size of the fish. The larger the species, the later, as a rule, maturity begins. At the same time, fish of the same species ripen at the same time, but depending on the growth and, therefore, on the conditions of their maintenance. By the time of sexual maturity, the fish should grow at least half the maximum size. The terms of sexual maturity of some species, as a rule, are indicated in the literature for aquarists, who need to have such information in order not to require the fish impossible - not to spawn not ready-made individuals.

The issue of sex differences is of interest to almost all aquarists. Strangely enough, it is possible to put some females to spawn or, conversely, some males and wait for the result, since not all the fishes have clear gender differences. But in many species, sex differences are well expressed. For example, in fish that do not care about their offspring, the females are larger, the paired fins and anal fin are much longer in the male, and the dorsal is pointed. Shark barbs (shark balacioheilus) and Akantoftalmus Kul hardly notice differences in the shape of the trunk in the ventral part. The female of the acantophthalmus has a shorter head than the male, and fewer pectoral fins. In azure nanochromes, the male is somewhat larger than the female (the fishes that protect the offspring), the forehead is slightly steeper (in many cichlids, the male is a fat growth on the forehead, which makes the latter look steeper and more powerful than the female), and the sperm conduit is small, (In the female the ovipositor is larger, has the shape of a truncated cone). These signs (and also longer and pointed anal and dorsal fins in the male, the pear-shaped ovipositor in the female) are characteristic of many species of the family of cychlasts.

To better identify the sex of the fish, you need to wait for her sexual maturity. During this period, cichlids (and also the scalars) are separated from the flock and create monogamous pairs, starting to prepare a place for laying eggs, driving away other fish (including their own species). In many species, spawning appears in spawning. So, the Brazilian geofagus becomes ashen-black abdomen and the lower part of the snout. Males, guarding offspring, as a rule, are larger than females. In many species of fish, males are brighter colored than females (notobranchies, guppies, fire barbs, lalius, glass perch, etc.), or, conversely, females are brighter than males (parrots, for example). In some cichlids the female and male are painted beautifully, but have a different color. For example, in the pseudo-pheromone pseudo-pheromone adult males are orange-colored, and the females are bright blue (the fry is colored like a female). In the yellow-blue pseudotrophaeus and pseudotrophaeus, Sokolof, on the contrary, is a blue male, and the female is yellow. Polymorphic form - zebra pseudotrofeus has about ten variants of coloring - from white and blue to orange and red, while the male, for example, can be blue, and the female itself is red. In a word, if the name of the species is precisely known, it is difficult for an adult female and a male to confuse such fish.

It is much more difficult to determine the sex if the fish have a completely identical color (from viviparous it is, for example, pecilia, mollynesia, pripelella, formosa, from the haracine - neon, ornamental, tetragonopteryts, pezili-obricones, carnegenols, etc.). In this case, it is necessary to distinguish the sex according to the shape of the fins, if there are such differences, or even in the shape of the body.

Preparation and selection of producers for spawning.

The initial selection of producers for spawning is based on observations of their behavior in a common aquarium. Select fish that show interest in each other. Often, for the first spawning, not a pair (female and male) is selected, but a nest, that is, one female and two or three males, for example, when spawning barbs, spotted catfishes, zebrafish, or, conversely, more females and smaller males (for example, When spawning cardinals). Such fish, such as danioriorio planted to spawn in the flock. Later, when the producers show their activity and mutual desire to participate in spawning, it will be possible to confine oneself to a couple, especially since males (for example, barbuses), carried away by the forthcoming tournament, are distracted and can "forget" about the female. It happens that it is necessary to plant fish of different ages for spawning. So, the males of Sumatran barbs should be older than females as much as possible.

The readiness of fish to spawn is evidenced by the appearance of nuptial coloring, as well as the nature of behavior. Scalarias and many other cichlids are separated from the general group in pairs and, having selected a certain site in a spacious aquarium, begin to thoroughly clean the plane of the leaf; Other cichlids also carefully clean the surface of the stone or wall of a specially installed flowerpot, ceramic tube, etc .; Geofaguses and parakeets begin to drag sand and pebbles through their mouths, so much so that a pit may form on the elevation and vice versa; Male barbs enter into each other in short skirmishes; Males of goldfish harass a mature female, adhering to its oviposition.

If the fish are healthy and the aquarium is fairly spacious and in moderation populated, planted, well-groomed, spawning is possible in a common aquarium, and not only viviparous species, but also spawning, protecting their offspring. However, in all cases it is not possible to conserve caviar: barbs, danios, catfishes, for example, eat it. That is why they resorted to planting fish for spawning in specially manufactured containers.

Transplanting the producers from the general aquarium into the spawning grounds, one must remember that the impact on the fish organism of a sudden transition to the environment with other indicators may prove to be so strong that instead of spawning it will cause a shock, which often results in the death of the producers, whose training took so long: For example, neon fish feel great in water with rigidity of 8-10 ° and even higher, and spawning in such water is impossible; Water in spawning tanks for them is very soft (up to 2 °). Experienced aquarists therefore recommend that for fish whose water composition in the spawner should be sharply different from the composition of the water in the common aquarium, make a smoother translation, setting them first in a buffer vessel (having indicators average between the total aquarium and spawning), at least 3-4 hours. True, there are opponents of such methods, claiming that a sharp transition "shakes up" the body and serves as an incentive for sexual activity. But we still think that such a "shake" a good result will not.

If the spawn did not work well at the first attempt, do not be discouraged. Many of the fish are ready for fresh spawning in two weeks. And here it is necessary to know the features of maturation in females of a new portion of caviar. Studies of ichthyologists show that until the fish completely dissolves (resorbed) the eggs left in the body after the previous spawning, a new portion of the caviar is not formed: the body must necessarily get rid of the unseen caviar.

Aquarium fish of some species are able to spawn eggs in the absence of males. So, the female goldfish, ripe for spawning, can sweep caviar, floating through thickets of plants. If the fish can not get rid of the caviar, the egg shells are destroyed and their contents are combined into a common mass. Inexperienced aquarists accept females with a belly swollen from such a liquefied mass, for ripe for spawning and vainly try to "force" them to spawn. With the resorption of degenerating eggs, the substance can dissolve, after which the fish restores the ability to reproduce.

Stimulation of spawning.

In natural conditions, spawning is stimulated by some or other factors that trigger a complex mechanism regulating the maturation of the sexual products of fish and the spawning process itself, accelerating it or delaying it. Without stimulation spawning can not do and in aquariums. Sometimes it happens by accident. For example, replacing a large amount of water in a common aquarium noticeably activates many fish, provokes matrimonial games. But most often, working with producers, the aquarist tries to reproduce (at least mentally) the situation that accompanies the fish in her homeland. For this purpose, as already mentioned, it is useful to analyze the natural conditions of local water bodies, the speed of the current, the composition of the water, the terrain and the bottom of the reservoir, the composition of rocks, the flora and fauna surrounding the reservoir, and, of course, the dynamics of climatic and Hydrological conditions in the habitat of the species. If you know in which case the species belongs to or what kind of family it belongs to, then it is possible to orientate your actions with a sufficient degree of accuracy during breeding.

What are the incentives used by aquarists, working on fish and wanting to provoke spawning?

Change (shortly before spawning) of the feeding regime, transfer (weeks to two before spawning) to abundant food, mainly live food. The increase in the amount of live food corresponds to the same event during spawning in natural reservoirs, and old aquarists advise to feed growers not only with moth, enchitraea, but also introduce small fodder - small crustaceans, for example, a vivipar. Increase the frequency of changing water to fresh, rich in oxygen, which also corresponds to what happens in nature. During the rainy season, the melting of snow in the mountains, fresh sources of oxygen rich and soft (not rich in salt) water are opened. The substitution of water can be increased already in a general aquarium or in aquariums, where males and females are planted before spawning. Sometimes the substitution of water is produced directly in the spawning tank, where the producers sit. In any case, the substitution of water should be accompanied by an increase in the oxygen content in it. If the water is boiled, then it should be properly aerated before use. It is noticed that the addition of cold fresh water stimulates spotted catfishes more if it coincides with a decrease in atmospheric pressure. While diluting the lemon tetra, the stimulus is, on the contrary, an increase in atmospheric pressure.

To create and maintain at a constant level for several days the desired water temperature is difficult without an electric heater in a single circuit with a thermostat. When breeding fish, as well as with their maintenance, it is impossible not to take into account the volume factor of the vessel. As already mentioned, some fish in cramped conditions refuse to give offspring. Partly the lack of water volume can be compensated for by its flowability or increase in water exchange.

Temperature regime.

For some fish species, in the spawning aquarium, the water temperature is raised by 2-4 °, which stimulates the maturation of sexual products in fish. This temperature is maintained at the same level not only during spawning, but also during the incubation of eggs, development of the embryo, larva and fry. Only after the water is gradually cooled. Sharp unplanned drops in temperature can lead to the death of fish larvae.

But not always the temperature regime should change in the direction of increase. After a rain in a hot climate does not always bring water warmer than in a pond. In the savannah, for example, in the drying reservoirs, where the eggs of the spawning carp fish are waiting for their hour, the temperature first decreases and only then, when the rainwater warms up under the rays of the hot sun, rises. When breeding catfish, stellar ancistrums, the temperature in the aquarium is reduced from 26 to 20 ° C by adding water to the spawning grounds, 4 ° colder than in the aquarium. The same stimulation is used for pearly gourami, and for speckled catfishes, a decrease in temperature is achieved by the addition of cold water, without switching off the heating, thus creating temperature fluctuations.

If an aquarium lover is interested in observing the spawning process (and this is a fascinating sight), then it is necessary to do this unnoticed for the fish (and certainly not to get into the vessel in order to fix something or catch someone). Everything should be thought out in advance and carried out so carefully that it did not have to interfere in the midst of the mating games. For example, the front (viewing) wall of the aquarium can be veiled with translucent paper (tracing paper) through which from a distance it is possible to observe the behavior of fish perfectly. If there is no soil at the bottom (which is typical of spawning aquaria), then it's good to put black paper under the aquarium - the dark bottom will scare away the fish less. As for the substrate, it must meet the requirements of the species, the biological characteristics of reproduction (and with this we have already introduced you).

For some species of fish, an additional incentive is to lower the water level compared to the usual and use a shallow aquarium, but with a large bottom area.

Light serves as a powerful factor stimulating spawning, causing pituitary brain reactions in fish that affect their behavior. In nature, spawning often coincides with an increase in the duration of daylight hours (correspondingly, the temperature increases and the rapid development of fodder crops).

Use a small amount of water from another aquarium, where another pair spawns (possibly of the same kind, but more willing to spawn). Sometimes there is enough glass of water from the aquarium, in which spawning, for example, barbs, to spawn in another aquarium.

Relationship between the season of the year and the activation of sexual activity of fish.

Is there such a connection? It seems that isolated aquarium conditions, a controlled environment in which fish live and spawn, allow them to get offspring at any time of the year. Many factors that affect the mechanisms regulating the maturation of the sexual products of fish and arising in nature at a certain time in the aquarium can be reproduced almost always. And yet there is one factor that can not be ignored and which depends on the season. This is an absolutely unique quality, which has a live feed in the spring. The composition of fodder in spring is one of the powerful stimuli for the maturation of sexual products. Feed in the spring is not only rich in nutrients, but also appears in large quantities. Together with the live spring feed, we bring to the aquariums information that a good time has come for spawning.

A good readiness for spawning is manifested in fish and in the autumn, as during the summer they manage to accumulate in the body the biological resources necessary for this. However, the care of providing fodder for fry makes us give preference to the spring time, especially when such highly productive fish, such as gold, tetragonopteryts, gurami, are bred.

Other parameters may influence the stimulation of spawning, for example, the content of humic substances in water (introduced as decoction or peat infusion, alder cones, oak bark and a number of other products). All the above incentives should be applied in a complex, observing a sense of proportion. For example, one should not get carried away by experiments with acidification of water in large limits, when it is sufficient to have a weakly acid medium for spawning.

Conservation and rearing of offspring.

In many cases, maintaining and growing offspring is no less difficult than preparing the producers and inducing them to spawn. Many fish, for example, neon, glass perch, willingly spawn. But ask, how many then manage to save caviar, larvae, fry, and raise the offspring to such an age to be calm for his future fate. An aquarist who does not know the "rules of the game" will not make much progress in breeding even such prolific fishes as barbs, gurami, danio, tetragonopteryts.

The most important thing to know is that the main condition for the normal development of the embryo and larva is the continuous supply of oxygen. Recall that the way and place of egg laying by the producers predetermine the oxygen conditions for the development of their offspring. Salinization of the caviar, its dullness inevitably lead to a decrease in the oxygen content at the outer surface of the egg shell, which is accompanied by a worsening of the incubation process. From the moment the eggs enter the water, their gradual swelling occurs. It should be noted that the strength of the egg shell simultaneously increases. Swelling of the eggs and lagging of the shell from the yolk surface begin after the spermatozoon has time to penetrate into the egg, since spermatozoa lose their mobility with external fertilization for a maximum of 5 minutes, while the spermatozoa remain the most active in the first minute, but also the unfertilized egg first Develops like. The speed of the sperm movement depends on the temperature, but since their energy reserves are limited, an increase in speed with increasing temperature shortens the period of mobility. The spermatozoon penetrates into the egg through a special opening - micropyle. Through the micropilar canal of the sperm reaches the cortical layer of the egg, and its head plunges into the cytoplasm. At the same time, a true gamete connection occurs, i.e. fertilization, after which the micropyle opening is blocked from penetration of other spermatozoa. Thus, polyspermy in fish with one micropyle (bony fish) can not be.

From the moment of fertilization of eggs, the individual development of the fish organism begins-ontogeny and its first period-embryonic (embryonic). The fertilized egg, and in the future also the fetus of fish, although they develop in the aquatic environment, but do not have direct contact with it. The supply of oxygen to the body of the embryo is provided by mixing the perivitellin liquid, this task is performed by the embryo performing periodic movements, which are called embryonic motility. Moreover, a high level of motor activity (the number of movements it makes per unit of time), small respiratory surfaces of the body, a small amount of blood is characteristic of fish embryos, in which development occurs naturally under conditions of abundant oxygen in the water that ishes their eggs during incubation. Such eggs usually have a weak color due to a small amount, and in a number of cases - a complete absence of carotenoids (yellowish or reddish pigments). If the normal natural condition of fish is a low oxygen content, then the embryos have a low level of motor activity, the presence of a significant amount of carotenoids and eggs is more intensely colored, the embryonic system of the respiratory vessels is developed, the appearance in the blood plasma is earlier.

The development of the embryo at the beginning of the embryonic period takes place inside the egg shell and in this state it is called an embryo. Embryos are sufficiently protected by shells. In some fish, eggs have two shells: the inner shell (radial), which serves mainly to protect the egg from mechanical damage and provides its moisture and gas exchange with the external environment, and the external one, which in many species of fish becomes sticky and eggs when it enters the water Is attached to the substrate. As far as the protection of the shells is reliable, one can judge by the example of eggs of some species of spawning carpubs, which has three shells. External, sticky, encrusted with grains of sand and acquires striking strength at the expense of the internal, which stands the cemented sphere. Between these shells and a special shell covering the embryo, there is a physiological fluid that prevents the drying of the eggs. These eggs resemble the eggs of terrestrial insects and reptiles.

Unfortunately, not all types of fish embryos are reliably protected. In most cases, during the incubation period, the aquarist must apply measures that ensure the normal development of live, fertilized eggs. As a rule, a lot of caviar in the aquarium after spawning is dead, within a day it completely whitens. On the dead eggs, very soon a fungus develops, which can move to neighboring live eggs while eggs. In addition, the incubation period can last for several days. It depends not only on the type of fish, but also on the temperature of the water. If barbs, zebrafish, tetragonopters and other haracin fish for development and hatching of the larvae are sufficient for a day or two, then this period lasts from 5 to 10 days for catfishes. To preserve eggs with a long incubation period, solutions of methylene blue, rivanol, malachite green, oxalate of bright green (in very small doses of 1-2 mg / l) are introduced into the vessel. In any case, it helps in the preparation for spawning of water, plants, substrate, aquarium, equipment, as well as the fish themselves, which should be stopped for 24 hours in order to release stomachs and intestines in a common aquarium. Nevertheless, it is seldom possible to achieve complete sterility in spawning.

If there is a lot of unfertilized, dead caviar, it is necessary to remove it as early as possible or to pick healthy eggs (transparent, without signs of whitish opacities) from the deceased, looking through the shallow glass vessel to the lumen. This can be done with the spawning of barbs, zebrafish, gold and other productive fish that have sticky eggs and are not afraid of bright light. In this case, the aquarist kills two birds with one stone. First, all the selected eggs (they are taken with a pipette with a melted end) in a clean vessel and fresh water (of the same composition and temperature as in the spawner) develop with almost 100% yield; Secondly, the productivity of fish is becoming known.

From the moment of hatching from the envelope, when developing in a free state, the embryo is called a prelariety, or a free embryo. The nutrition of the larvae at this stage of development continues at the expense of the energy content of the yolk sac. In most cases, the larvae have an adhesive gland on the head (occipital part), by means of which they attach to the glass of the vessel, to the plants. Many are lying on the bottom. By the time of complete resorption of the yolk sac, the larvae begin to move actively, and they immediately need the introduction of the first (starter) food. Such food can be infusoria-shoe, rotifers (which are part of the so-called "live" dust). In some cases, egg yolk (diluted in water and very small doses) is used as a stern. But the fish farmer should remember that the lack of food in the first hours of transition of larvae to free swimming after resorption of the yolk sac may lead to partial or complete death of the offspring. In general, if the aquarist does not take measures to preserve the offspring, the losses can be quite large. They begin already during spawning. Watch how greedily barbs or zebrafish sprinkle on their own eggs in the spawning aquarium. They will not calm down even when the eggs drop to the bottom or stick to the substrate. To save them on the bottom of the aquarium you need a protective net. The larvae of viviparous fishes have found convenient protection. They, as is known, also develop from caviar, but this happens in the mother's body and they go out into the light completely formed.

Some fish themselves protect their offspring. The most caring cichlids. The male and female in a common aquarium, inhabited by other, far from harmless fish, are able not only to protect the eggs, but also to grow fry, what they do with enviable selflessness, sometimes slaughtering larger individuals who have encroached on their babies' life, to death. During this period, the fish lose their sense of fear and rush to the net, bite the lowered arm into the water. They carefully and operatively hide (lodge) the larvae, fry even at the slightest suspicion. Among cichlids there are species (for example, haplochromis, trophies, laboteotropes, melanochromis), the females immediately after spawning take the pitted eggs in their mouth, where they are incubated for a long time (in some 10-12 days, for the others 22-26 days) in the laryngeal Bag. Protect, their offspring and males of labyrinth fish until the moment when the larvae swim. Then the male must be removed, since he can eat "disobedient", larvae spreading in all directions.

Fish, guarding offspring, closely monitor the masonry, remove the dead eggs in time, carry the larvae to a new place, leaving the decaying shells of eggs on the old one. Moving, as if chewing eggs, the female simultaneously bathes them with a current of water. The eggs of the eggs are fanned by fins. Creating an influx of fresh water.

Specifically, we should dwell on the peculiarities of the conservation of eggs of certain spawning carpubs, the so-called fish of drying reservoirs. These fish lay eggs in the muddy soil of the reservoir, which completely dries up. The period of drought they experience in a state of diapause, and with the onset of the rainy season and the filling of the reservoir hatch formed fry. For the normal development of caviar of such fish, it is necessary to lie without water in a moist substrate for several weeks, and in some cases several months. In aquariums, these fish lay eggs either in fine sand or in peat crumbs. For incubation, the eggs are separated from the sand, sifting it through a sieve (the sand passes through the sieve, the roe remains), and transferred to a substrate (peat). If the fish have laid eggs in peat, water is drained from it through a nylon net (if the egg shells are solid, peat can even be squeezed out slightly in the net). Then the substrate with caviar is dried. Aquarists not only take away the eggs laid on the substrate, but also in the females that incubate it in the mouth. They do this because it is difficult for them to withstand a prolonged starvation in an aquarium and not succumb to the temptation to swallow food, and with it, caviar. Although many recognize that the developed instinct of preserving the offspring often overcomes the feeling of hunger. It should be noted that the female with caviar in the new aquarium must be carried along with the water, holding her hands tightly in the tube, in which she hides. Some large cichlids, laying eggs on a stone or on the wall of a pot, spawn are selected if the producers do not have a stable parental instinct. Having quarreled, they can eat caviar or larvae. These examples from the point of view of biology can be attributed to the not quite normal, arising in the conditions of the aquarium. Often this behavior is provoked by our rude interference, awkward actions, then the fish eat offspring in spite of their natural logic, not seeing the possibility of keeping it safe. When incubating calf eggs and other cichlids next to the substrate with caviar laying, a constantly running sprayer is always placed, creating a continuous movement of water.

Aquarists are increasingly turning to methods and designs used in industrial fish farming (for example, similar to the apparatus of Weiss). The main principle of the action of such incubators is the constant mixing of eggs with a stream of air or a current of water, purification of water in biological filters and degeneration systems. The water enters the incubator after thorough cleaning in the biofilter system. The fact is that Malavi cichlids, for example, are susceptible to the disastrous effect of bacteria and from one dead egg left in time can die all the rest.

When all the difficulties with the caviar are left behind and the dash of the transparent larvae with tiny air bubbles glows brightly through the vessel (it is clearly visible on the lumen), the most important period is probably the first one, on which very much depends (there is a large withdrawal, and sometimes Complete death of all offspring). About fodder and fodder crops is described in detail earlier. Here we will dwell on specific points. Many species are not demanding for the choice of the first food, any small traditional fodder is suitable. However, there are species whose fry due to their physiological characteristics require a strictly defined food, the absence of which will ruin the entire litter. Neon, for example, any traditional food can not be given because of their susceptibility to infection by bacteria and harmful infusoria. In the spawning area, it is not possible to introduce unrefined crops and substitutes for live feeds that pollute the water.

Fish, which have uneven growth, should be sorted, transplanting large ones into a separate aquarium. It is not recommended to mix fry of different ages and different species before they grow to 1/2 - 1/3 of the size of adult animals or will not switch to food by bloodworms. Abundant feeding of young animals inevitably causes rapid contamination of the aquarium and spoilage of water. The aquarist, if he does not want to lose the young, is obliged to remove the remains of the feed and replace the water. Fry of different species of fish behave differently. Some do not fit even close to the end of the hose during collection from the bottom of the contamination, others are not so careful and can die, so the methods of caring for the vessel with fry apply different. Some aquarists advise to keep in an aquarium with fingerlings of snails red fiz which pick up the rests of a forage; Some recommend feeding the fry at an early age in the incubators of the Weiss apparatus. But when feeding juveniles haratsinovyh fish clean the aquarium every 2-3 days. Since it is impossible to suck dirt from the bottom and walls (together with water the hose seizes live fry), it is necessary to pour the contents of the vessel with the fry into a small enameled basin. Twisting the water in the basin, it is possible to collect debris in the center (the fry spreads closer to the walls) and suck it with a siphon (a PVC pipe with a diameter of about 4 mm) together with a large part of the water. A small amount of water with fries is returned to the aquarium prepared (washed and filled with fresh, standing water of the same composition and temperature). All operations for cleaning the aquarium with fry, releasing it from the accumulation of organic substances require compliance with the main rule: it is impossible to tolerate sharp changes in the characteristics of the habitat. The transfer of juveniles from spawning and incubation temperatures to lower levels, the release of vessels from medications, and the increase in water hardness should be carried out smoothly, by replacing water with fresh water in small portions.