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Tsikhlazomy north - large tall cichlids - were very popular with us about 15-20 years ago. Then they were also called false discus. True discus - gentle and capricious fish - it was not easy to keep, and unpretentious "ersatz-discus" perfectly felt even in the aquariums of beginners. Later, with the onset of species abundance in domestic aquaristics, the northerners withdrew to the second or even to the third plan. Which, by the way, did not make them less interesting.
By the discus, even the false, adult cichlazome, the north can only be called with great stretch - the shape of its massive body, strictly speaking, is far from an elegant flat disc. However, with all the obvious differences, these two taxonomically distant species have many common features. But the funniest thing is that the northum, apparently, is not even a cichlazom.
It must be said that the genus Cichlasoma in general is very unstable systematics. At one time, it included many species of large and among similar South American cichlids of similar morphology, which in subsequent classifications were identified in other genera. So it happened with the north opened in 1840. According to the main morphological and anatomical features, it seems to be closer to Cichlasoma, but some scientists consider these fish to be representatives of the genus Heros (Heros severus). Nevertheless, in most publications on aquaristics, it is still called Cichlasoma severum (Heckel, 1840).
Severum in translation from Latin "severe", but not in the meaning of "angry", but rather "restrained." This characteristic is addressed to the exterior of the north - a dense body of gray-brown color with olive-tinge, higher than most cichlases, on the sides small brown claws, large spots on the last soft rays of the dorsal and anal fins are connected by a strip at the base of the tail. Dorsal fin from olive-green to almost black, anal - with reddish top, tail - gray-green. On individual scales, more or less pronounced bright markings are yellow or pinkish. In aquarium northerms, a wide range of intensity of color - there are both bright enough and very faded specimens, males are usually brighter than females. In culture, there is a red variation and a golden-pink albino form.
The species adjective "severus" can also be interpreted as "sevrene". Indeed, these fish inhabit the reservoirs of the northern part of the Amazon basin. They are acclimatized in the south of Nevada. In nature C.severum reach 20 - 30 cm, in the aquarium - 15 - 20 cm. Their flattened body is ideally adapted for living among dense vegetation, interlacing roots and branches of fallen trees. Depending on the habitat, their natural color varies from olive-yellow to almost black. Severums do not belong to the dominant predators and prefer to stay in the thickets - both for safety and for the convenience of hunting. However, since their content and breeding are not problematic, the aquarium population has not been replenished for many decades with captured specimens.
To keep fish fit vessels of 100 liters. The more spacious the aquarium, the more the size of the specimens grown in it will correspond to the natural one. The form of the body of the north is in some dependence on the configuration of the aquarium - in flat and high shields they grow more discoid, in wide and low "troughs" - with an elongated body, more similar to classical cihlaz.
They are quite loyal to the water flora, because they are neither convinced vegetarians nor zealous soil diggers (although the leaves and roots of tender and soft plants like aponogetones and ampullas may well suffer).
The overwhelming majority of conflicts, which are not too hot, are of an intraspecific nature, but with neighbors, even much smaller, they get along well. In the aquarium of one of my acquaintances, several of the northern lands lived peacefully in the midst of the thornets, sorting out, minors and other characine trivia. Although it happens, over the years their character begins to deteriorate, especially in close vessels. As categorical contraindications can be called unless the neighborhood with the goldfish - their fluttering veil fins act on the north as a bullfighter's cloak to the bull.
Usually the northern people are taken for hunting only from hunger, but not from excitement. And they like to eat and obviously prefer animal food. Earthworms, insects, large bloodworm, enchitrea, tubule, meat, seafood, again small fish - this menu is quite consistent with the high level of metabolism of these fish. The latter, by the way, necessitates the regular substitution of a third of water and the presence of a biofilter.
The northern composition of the chemical composition of the medium is not exacting. The recommendations of different authors vary from the soft weakly acidic water characteristic of the Rio Negro to the neutral dGH within 10-20 degrees. Thus, these fish can be maintained both in classical conditions for South American water reservoirs, and in fairly hard water along with African cichlids. The main thing is the freshness of the water and sufficient oxygen saturation. The optimum temperature is 24-26 degrees C.
With a life expectancy of up to 15 years, sexually mature fish become in the second to third year. By this time, the group is divided into pairs and begins to divide the territory. And with a lack of males females can form pairs with each other. One of the females takes on the role of the male and thus the entire spawning ritual: courtship, protection of the territory, preparation of the substrate, etc. - fully complied with. But, unlike, for example, from ancistrus, the females of which, if necessary, can really change the sex, in the northerners such metamorphoses are only behavioral.
Postponed pseudo-steam caviar, of course, remains unfertilized and is soon eaten by the producers. Such "pink" games, by the way, are peculiar to many cichlids. The males that remain in the spawning period without a pair do not engage in such "roughness" and either behave indifferently or choose the "bachelor's corner" in the aquarium and for some time they do not let anyone in there, "sublimating" the unrealized instinct.
Sexual dimorphism in the severum is poorly expressed. In males the body is more massive, the frontal part of the head is heavier, the ends of the dorsal and anal fins are elongated into the braids; Color often turns brighter, for example, the head is decorated with a so-called mask - a greenish-turquoise pattern on the forehead and gill covers. In females it is expressed only as an easy tide.
An indication of the readiness of fish for spawning is the increase in the ovipositor of females (it takes the form of a truncated cone) and swelling of genital papilla in males.
Incentives for spawning are traditional - intensive water substitution, increased aeration and temperature rise up to 26 - 29 ° C. According to some data (S. Kochetov), ​​spawning can be triggered by the presence of microcream - rotifers, nauplius, etc. in the water. Adult individuals can not feed them, because the micro-organism passes through the gills, but is perceived as the fodder base for future offspring.
Like other flat cichlids, the north form an open laying of caviar, the optimal substrate for which is a flat inclined surface, for example, stone, clay crocks, a piece of plastic. Some couples prefer them to the aquarium glass or wide leaves of plants.
Day or two the couple prepares the chosen place. At this time, the north are becoming aggressive and anyone invading the territory occupied by them is mercilessly driven. However, this aggression is local: the fish do not pursue violators of the border along the aquarium, as a result, before the serious injuries of neighbors, it usually does not reach the point. A complex and interesting spawning ritual, which all cichlids are famous for, includes joint cleaning of the substrate and "dancing". Severums often twist their heads together - sentimental observers find this spectacle very touching.
Masonry consists of about one thousand eggs attached to the substrate. From this moment the duties of the parents are usually divided: the female pays more attention to caviar, carries out the "cleaning of the ranks", removing the unfertilized and whitened eggs, and aerating the masonry with the movements of the pectoral fins. The male is oriented mainly to protection and protection of the territory. However, this is more a tendency than a general rule: in fact, the distribution of responsibilities in each pair is individual.
In general, for fish, a long time in the aquarium culture, there is a certain reduction in the parental instinct. This is not surprising, because in nature couples who do not care for their offspring have no chance to pass such a dubious dignity by inheritance, because it, this offspring, is simply eaten. But professional breeding using an incubator equalizes the chances of preserving the genotype of both good and bad parents. So do not be particularly surprised if on the second or third day the fish suddenly destroy their own eggs.
To reduce the likelihood of such a turn of affairs, during the courtship for the offspring the couple must be protected from any stresses, although this is not fully guaranteed. If the goal is precisely the production of offspring, and not the observation of the manifestations of the parental instinct, it is better to remove the substrate with caviar from the common aquarium and place it in the incubator, preferably under the flow of small air bubbles.
Incubation lasts from 5 to 8 days, depending on the conditions, mainly temperature. The lower the temperature, the later the larvae hatch and the larger they grow. But if the temperature is significantly below optimal, then the young are more likely to have cases of scoliosis and other malformations.
When hatching occurs in the presence of parents, an aquarist may be waiting for a rare, but very pleasant surprise. The fact is that some pairs of northerners are able to feed their larvae with a mucocutaneous skin secret in the same way as real discus (and according to unchecked data - and scalars). If the owner is lucky, such a "milk" couple will decide for him the problem of starting feed: the larvae attach themselves to the broad sides of their parents and live for several days due to nutritious mucus. Well, after weaning from the sides, when the young begin to swim freely (4 to 7 days), zooplankton of the appropriate size is used: rotifers, Artemia nauplii and Cyclops, microcircumstances, etc.
At first, the fry grows not very fast, reaching about a centimeter by the month. At this time it becomes obvious that the appearance of the young northerners is more reminiscent not of their own parents, but of "godfathers" - discus. The juveniles have a flat and high discoid body of grayish-olive color, painted with seven or eight dark vertical bands - this color is ideal for camouflage among thickets of plants and wood fragments.
Having not yet had enough experience "kettle" in the Bird Market, it is quite possible to sell the gentlemen of the northern age as real discus (this is much more likely than the famous story about the sale of a piglet under the guise of a bull terrier puppy). So the name "false discus" adopted among aquarists is still valid.
Closer to the three months of the young, the juvenile moves on to feed with bloodworm, tuber, scraped meat and other "adult" food and begins to grow much faster. Feeding the coronet to the northerners in general, and youngsters of this age especially, are less suitable - for active growth, the necessary nutrients are lacking in it. In the growing aquarium should be more carefully monitor the purity and freshness of water - intensely developing adolescents pollute it very quickly.
The patronizing striped color of juveniles of prepubertal age, which is kept by a flock, disappears approximately to the year of life. In adult individuals, usually only one band at the base of the tail is retained, the others, if present, are very pale.
So, although tsikhlazoma north is not a fashionable species, these fish can be safely recommended as very interesting and grateful pets. Quiet, peaceful nature and at the same time the ability to stand up for oneself allows to keep them in the most diverse species communities.
The unpretentiousness to the conditions of keeping, the ease of breeding and the bright individuality of character make these fish ideal objects for neophyte aquariums. Well, those lovers who just watch the fish enough will appreciate the ability of the north to make tactile contact - they can easily be trained to take food from their hands and even give themselves to pat.
Such a pleasant friendly dialogue with these good-natured "aquarium cows" can bring a lot of pleasure.


E. Timonov, Moscow, Aquarium No. 3, 2001.