Aquarium fish "knife black": content and care (photo)

Among the huge aquarium variety, one of the most interesting is the fish, known as the "black knife". Officially, she's called an apteronotus, and in English-speaking countries her name is "black ghost." Aquarists with experience willingly put such an exotic in their glass basins. But beginners, perhaps, need to gain experience before venturing into such an acquisition: a black knife is a fish, the content of which requires special attention and skills.

Where did the apterotonus come from?

This exotic fish is home to the South American continent, where she mastered the expanses of Peru, Brazil, Bolivia, Colombia - the upper and middle of the Amazon. And in Paraguay a black knife is found in the Parana River. He prefers reservoirs with a weak, unhurried flow and rich underwater vegetation. The waters are dull in such places, their visibility is very low. Therefore, the apteronotus has a very weak vision, but there is an alternative way of navigation - weak electrical impulses, the source of which are white rings that surround the tail. In their nature, the black knife protects itself from attack and seeks food. In aquariums apteronotus has appeared very recently - only about twenty years ago. But I've already gotten myself started.

Appearance

In the home "pond" aquarium fish "knife black" can become its decoration. Smooth, soft outlines and plastic movements, even in people indifferent to aquarium, immediately attract attention. The apteronotus grows up to fifty centimeters (if, of course, it lacks space). The absence of scales gives the impression that the fish is velvety, and makes its color deep and soft. The back does not have a fin in the fish, but the anal extends along the entire abdomen. Thanks to this structure, the black knife can swim in any chosen direction, correcting its movement with the pectoral fins. A very common phenomenon is when the apteronotus floats on its side. If a person before had only other fish, in which such behavior indicates ill health, the aquarist may suspect something is amiss. But for knives this style of swimming is an ordinary phenomenon.

We equip new settlers

If your attention is attracted by a black knife, its content will be successful only in a large aquarium, not less than 150 liters in volume. The lack of space not only does not allow it to grow to the possible sizes, but it also undermines health, weakens immunity and makes it more vulnerable to various ills. The temperature should be maintained at 23 degrees; When you reduce it to less than 18, you are guaranteed to lose the pet - the fish is tropical, thermophilic. A third of the water must be changed weekly. Moreover, the aquarium should be equipped with a reinforced aerator and peat filter. The "landscape" is made up by numerous shelters: the black knife is a night creature, in the daytime it hides, and there must be enough places for it. As far as lighting is concerned, it should be used more for underwater plants, since the activity of apteronotus only manifests itself at night, and its vision is weak. It's worth taking care of the glass lid on the aquarium: it's not uncommon for black knives to jump out of the water.

Food

In natural conditions a small black knife feeds on fry of other fish species and insect larvae, that is, it is carnivorous. At home, it is fed with live or frozen feeds: a pipe mill, a bloodworm. Quite willingly the knife black eats crumbled shrimp and squid. Dry food, like any substitute, fish ignore, until finally starved. In principle, it is possible to accustom them to such a diet, but it is impractical. Feeding is done once a day, after turning off the aquarium light. From overeating apteronotus often die, so you need to calculate the rate of your pet and give a little less.

Who to let in the neighbors

In principle, the knife is black - the fish is peaceful and non-aggressive. Clashes only occur between males of their own kind in territorial disputes. However, given the predatory nature, it is better not to add small fish to apteronotuses like neon and guppik: eat. To larger ones the knives are absolutely indifferent. However, it is better not to let too many moving fish in one aquarium with them - for example, barbs. Ateronotus are fearful, and from the excess movement around you can get stress. In addition, such neighbors can patch thin fins of black knives.

With regard to health

Since the black knife is devoid of scales, it is especially vulnerable to ichthyothyroidism. His treatment is complicated by the fact that categorically you can not use drugs in which there is zinc, so when buying drugs, you must carefully read what is included in their composition. The signs of the disease are:

1. White small hillocks from half a millimeter to one and a half in diameter. Aquarists call such a rash a manga;
2. Frayed or stuck fins - the sign is already secondary, indicating that the process has gone quite far. In addition, such a symptom is characteristic of other diseases;
3. Swelling of the body. Also observed with various diseases.

Ichthyophthyriosis in other fish species is often treated with water salting in the aquarium. But the black knife can die from such measures. Want - you can look for any patented means. However, it is checked by many - pretty and malachite green. It is harmless to plants, does not degrade biofiltration, so you can safely bring it directly into the aquarium water. The usual concentration for the treatment of ichthyothyroidism is 0.09 mg / l. However, taking into account the absence of scales in the apheronotuses, it should be reduced to 0.04 mg / l. Add the product to the water daily, before each addition a quarter of the water in the "pool" changes, and this is done until the "manga" disappears, plus two days after this.

Reproduction of black knives

Ateronotus is a viviparous fish. Breeding it at home is quite difficult and is rarely crowned with success. However, you can try. To do this, the selected pair is planted in a spawning vessel with a volume of 100 liters; The water temperature should be stable 25 degrees. At the same time you need to gradually add a little clean water - it's an imitation of a rainy season. Plus, provide a stream of water in which the caviar is laid. Upon termination of spawning, the parents are removed from the spawning grounds. After 2-3 days hatchlings will hatch. All this time we need to monitor the situation in the aquarium and clean the dead eggs.