Order: Carp-shaped (Cypriniformes)
Inhabit South America.
The body is moderately elongated in length, somewhat flattened laterally. Anal fin longer than dorsal. The caudal fin is two-bladed. There is a fat fin.
Neon red: keeping and breeding fish.
Photo: Paracheirodon axelrodi
Photo: Paracheirodon axelrodi
It lives in Venezuela, Brazil.
Sexual differences are weak. The female is slightly larger and sexually mature has a fuller abdomen.
Maintenance in an aquarium densely planted with plants. They like old, slightly peaty water and dark soil. Eat any medium-sized live and dry food. Flocking is preferred. When kept in water with a dH of more than 10 °, fish may lose their ability to reproduce. It is necessary to change 1/4, 1/5 of the volume of water 1 time in 2 weeks.
Water for maintenance: dH up to 10 °, pH 6.0-7.0, t 22-24 ° C.
Pair breeding. Spawning 10-20 L with spawning grate. Lighting is not required.
Breeding water: dH up to 2.0 °, pH 5.8-6.2, t 25-27 ° C. Carbonate hardness is minimal.
Before spawning, producers are seated and plentifully fed with live food. Neon red usually spawns in autumn, winter and early spring. It is noted that an increase in atmospheric pressure serves as an additional stimulus for spawning. Usually spawns at dawn in complete darkness.
Spawning can begin on the 3rd or 4th day. For more than 5 days, producers should not be kept in spawning, as they do not receive norms here and eat a significant part of caviar at later spawning. In addition, when the spawners are kept for a long time, the water quality deteriorates and it is difficult to count on a high percentage of larva yield. Of great importance for successful breeding of the species is the quality of preliminary disinfection of spawning and water.
Water for spawning is kept in the light with plants for 2-3 weeks, then disinfected with an ozonizer. After spawning, the producers are planted. Larvae appear in a day. The fry begin to swim on the 5-6th day, then they need to be fed.
Starter feed - rotifers and nauplii cyclops.
From the beginning of feeding, a sprinkler with weak blowing is installed in the spawning grounds. Little by little, more hard water from the aquarium, necessary for the normal development of fry, is added to spawning.
Aquarium red neon content
The fish are peaceful, kept in the middle and lower layers of water. The view is suitable for keeping in a general aquarium.
Keep in the aquarium red neon need a flock of 10-15 individuals. To feel the beauty of these interesting fish, the lighting in the aquarium should not be too bright. Floating plants are good for softening it. And to create the optimal spectrum of radiation, it is advisable to combine fluorescent lamps with incandescent lamps, or use special LED aquarium lights.
The light source should be placed on top, but as close to the observer as possible. Thus, we will direct the light at an angle to the body red neon. With such lighting, their color will be as expressive as possible.
Among the thickets of echinodorus, cryptocoryns and ferns, open swimming areas should exist in the aquarium.
Red neons in a species aquarium
Once or twice a month, it is recommended to replace about 20% of the old aquarium water with fresh water of the same composition, as well as pour it instead of evaporated. Keep the aquarium clean with red neon, because they do not tolerate turbid water and the presence of a large number of microorganisms in it.
Red neons not demanding on a large amount of oxygen, live well in an aquarium with well-developed living plants without any aeration. With this content and moderate feeding, it is easiest to maintain cleanliness.
No aquarium aeration per adult red neon 2.5-5 centimeters long requires 3 liters of water, and with aeration - 1.5 liters. The optimum water temperature is 23-25 ° C, and it is important not to let the temperature drop for a long time below 22 ° C.
Red neons quite unpretentious, water with the following parameters is suitable for their content: hardness dH up to 20 °, pH from 5 to 7.8.
Soft water is needed red neon only during spawning. The rest of the time, the fish live perfectly in hard water. As for the pH, if the aquarium is lit up too much, the water in it due to the intense absorption of carbon dioxide by the plants, at some point, can become alkaline (pH reaches 10). Under such conditions, the body of red neon becomes vulnerable to various diseases.
Red neons extremely susceptible to nitrite content in water. This compound is usually quickly converted to low toxic nitrate, and its content in the aquarium tends to zero. An increase in the nitrite content leads to the oxidation of hemoglobin to methemoglobin in the blood, which leads to a decrease in its oxygen capacity.
Red neons - sexual dimorphism
Sexual dimorphism in red neon, as in the case with other representatives of this genus is weakly expressed. With a total body length of adult fish 3.5-5 cm (up to 2.5 cm in nature), females tend to be larger than males and fuller (especially during spawning). In an adult female, the luminous strip is wider than in the male, and the edge of the anal fin has a deeper notch.
Red neons: above is a male, below is a female
Reproduction of red neon
As mentioned above red neon It is difficult to breed an untrained aquarist, because fry are extremely sensitive to lighting and water quality. They, like eggs, develop in an acidic environment (pH 5-6) and in low light conditions.
Spawning can be both doubles and flocks.
It is better if the spawning is completely glass, about 40 cm long, without soil, mounted on a dark substrate. The water level in the spawning - not less than 30 cm, as spawning passes very rapidly fish need a place to disperse. A separator grid is laid at the bottom, and willow roots and a bush of a small-leaved plant are fixed on it.
Water should be of the following composition: temperature 26-27 ° C, hardness up to 2 dGH, KH 0 °, pH 5-6.5, level 20-25 cm. With hardness values of 3 dGH and above, fish will not breed. In some literary sources, water is recommended to be disinfected with ozone or ultraviolet.
For spawning, you can plant fish at the age of 9-10 months. Some aquarists use one-year-old females and two-year-old males as producers. You can select a couple from a group of young neons based on their behavior - individuals who show a desire for spawning pursue each other.
Before landing in spawning, females and males are kept separately, about two weeks, at a temperature of 23 ° C. The diet in this period should be plentiful and consist of enchitreas. Such a diet stimulates spawning. The day before spawning, the fish are stopped feeding.
To spawn, producers are planted in the afternoon. In a room with a spawning aquarium, silence should be observed.
The incentive for spawning is a sharp increase in water temperature from 26 to 30 ° C in the morning and its gradual decrease in the evening. Spawning occurs in the predawn hours. The female tosses from 150 to 300 non-sticky eggs in the water column, and the male fertilizes them.
After spawning, the producers are removed from the aquarium, and the aquarium is darkened, as caviar red neon afraid of the light and perishes under its direct rays.
The incubation period lasts 24-32 hours. After hatching the larvae, dead eggs are quickly removed, and the aquarium is again shaded. After 4-6 days, the yolk sac is completely absorbed in juveniles and they begin to swim.
Since the fry red neon in a brightly lit aquarium they lose their orientation in space and are not able to eat, since they are genetically programmed for completely different conditions: life in the twilight of a rainforest, where individual sections of water are illuminated by rare narrow sunlight that hardly breaks through the thick crowns of trees.
Fry red neon they are inactive and see almost nothing (distinguishing only light from darkness), therefore they can fully feed only when they are in a cluster of ciliates. Nature gave them a pronounced desire to swim from darkness to light (this behavior is called phototaxis - movement under the influence of light). Ciliates behave similarly. Therefore, the aquarium with fry is closed from the sides and lightly illuminated from above the place through which they are given starter feed, which uses the smallest ciliates and rotifers.
In such conditions, fry find food without problems.
Gradually reduce the dimming, preventing direct light from entering the aquarium. At the same time, water hardness is gradually increased.
Puberty in red neon occurs in 7-9 months.
In nature, they live no more than 1 year, although they can live up to 5 years in an aquarium.
Red Neon Diet
Anatomy Features red neon confirms predatory way of food. Their stomach is voluminous, while the intestines are short, comprising two lengths of the abdominal cavity. For adults red neon It doesn’t require a lot of food, they easily endure fairly long hunger strikes.
In an aquarium red neon consumes any dry commercial mixes. It is advisable to diversify the diet by introducing live and frozen food. Small crustaceans (daphnia, brine shrimp nauplii) and bloodworms with coronetra are preferred. Not often, the diet can be varied with crumbs of white bread and semolina scalded with boiling water.
Feeding red neon
Analysis of the contents of the gastrointestinal tract of 80 wild individuals of Paracheirodon axelrodi suggests that representatives of this species are micro-predators of Walker, 2004. They feed mainly on micro-pupils and mosquito larvae. The fact that the presence of these organisms in the intestines is not accidental is evidenced by the relatively small fraction of the plant component (12.5%) and the presence of a large number of similar organisms in the stomach. Nevertheless, a small proportion of fish prefers mesofauna (rotifers, amoeba) (15%) and caviar (7.5%).
Features of the anatomy of red neon confirms a predatory way of eating. Their stomach is voluminous, while the intestines are short, comprising two lengths of the abdominal cavity.
In an aquarium, red neon consumes any dry commercial mixes. It is advisable to diversify the diet by introducing live and frozen food. Small crustaceans (daphnia, brine shrimp nauplii) and bloodworms with coronetra are preferred.
Results of the analysis of the contents of the gastrointestinal tract
Most branched crustaceans (a subclass of Cladocera) were represented by small, almost spherical mines (Moinidae family), but there were large daphnia (Daphniidae family) and some macrotrix (Macrothricidae family). Among copepod crustaceans (subclass Copepoda), benthic harpacticides (the Harpacticidae family) were especially distinguished.
The presence of mayfly nymphs (order Ephemeroptera), liceworm larvae (Ceratopogonidae family) and dipterous (Diptera), small flies or pupae with pigmented eyes (Dolichopodidae), small beetle larvae (Coleoptera), and half-rigid winged nymphs (Hemipidae) and Nemidae . The last food item indicates that the prey is also captured from the surface of the water, for example, small flies that have fallen or washed into the water. Undoubtedly, in indefinite fragments there were larvae and adult mosquito-bells (Chironomidae).
Other objects were represented by small-bristle worms and ticks. In three cases, it is not known exactly what the remains of newly hatched shrimp and fish larvae belonged to.
In the contents of 8 stomachs, rotifers were found (Rotifera), usually several in each. In 9 stomachs, a protected amoeba (Thecamoebae) was found. including Difflugiidae, Nebeliidae and Arcellidae.
The eggs in the stomach, for the most part, belonged to invertebrates, probably micro-gloves, but in two cases they belonged to vertebrates, possibly fish.
Among the algae, only unicellular diatoms Navicularia and Pinnularia, as well as several green cells (Conjugatophyta and / or Chlamydomonas, or single cells of small Volvocaceae) were noted. The contents of the stomach also contained multicellular, probably Tribonema (Xanthophyceae), but the cell structure also indicates the presence of diatoms.
Animal detritus includes muscle, membrane, and other non-victim protein tissues. Silver pieces of the membrane, black pigment and fish scales indicate that some red neons eat the remains of large dead fish. Some tissues belong to large dipterous larvae. Plant detritus primarily includes plant fibers, pieces of bark and leaves with fragments of decomposing mold, Hyphomycetes, and probably pieces of fruit. In some cases, the detrital cortex was stained in intense orange tones, indicating the presence of heterotrophic bacteria Chlanydobacteria (Chlamydobacteriales), accumulating iron oxide (Fe3 +).
In 6.3% of 80 opened fish, parasitic nematodes were found in the whole and stomach.
Compatibility with other types
From 6-10 individuals of Paracheirodon axelrodi should be lodged in the aquarium. They coexist beautifully with other schooling small characins, for example, Paracheirodon simulans, with which they partly share their habitat. As neighbors, carp, catfish, corridors, small freshwater shrimps, and discus are also suitable.
Red Neon Breeding
Sexual dimorphism of Paracheirodon axelrodi, as in the case with other representatives of this genus, is weakly expressed. With a total body length of adult domestic fish of 3.5-5 cm (up to 2.5 cm in nature), females tend to be larger than males and fuller (especially during spawning). The fish reach puberty at the age of 9 months. In nature, they live no more than 1 year, although they can live up to 5 years in an aquarium.
Presumably, the male (on the left, ill. Paleoglodit, mojbiljniakvarijum.org/forum) and the female (on the right, ill. Elma Ben, flickr.com) of red neon (increases by click)
It is difficult to breed red neon for an unprepared aquarist, because fry are extremely sensitive to lighting and water quality. They, like eggs, develop in an acidic environment (pH 5-6) and in low light conditions. Spawning can be reproduced both in a flock of individuals and between a pair (male / female). Spawning occurs in the morning. The female throws from 150 to 560 sticky eggs in the water column, and the male fertilizes them. After breeding, producers should be removed.
The incubation period lasts 24-30 hours. After 3-4 days, the yolk sac is completely absorbed in the young and they begin to search for starting food.
Selling ornamental fish from Amazonas is one of the most profitable areas of fish farming and accounts for up to 90% of all aquarium fish exports from Brazil. Most fish species are caught from flooded forests in the middle of the Rio Negro Basin. Their annual export reaches $ 3 million, accounting for 2% of the total export volume of the Manaus Free Economic Zone. Although ornamental fish sales make up a small part of the entire Amazonas foreign trade, it reaches 65% of the local economy of Barcelos, directly or indirectly involving 80% of 16,107 residents.
Over the past few years, fish exporters recorded a decrease in sales by 40-50%. This trend is due to several factors, for example, an increase in the supply of quality individuals bred in aquaculture, high mortality of wild fish, and low quality of exported species. From 30 to 70% of individuals caught from the Amazon die before they reach the final owner. One of the main causes of death is poor water quality.
Red neon is the most abundant species of aquarium fish (21%) in the middle of the Rio Negro Basin. In addition, it is most in demand on the world market, dominates the aquarium market in Brazil and represents up to 80% of all fish caught in the state of Amazonas. Unfortunately, 40 out of 50 boxes of red neon coming from South America to the United States are lost due to the death of individuals.
1. Sarah Ragonha de Oliveira, Rondon Tatsuta Yamane Baptista de Souza, Érica da Silva Santiago Nunes, Cristiane Suely Melo de Carvalho, Glauber Cruz de Menezes, Jaydione Luíz Marcon, Rodrigo Roubach, Eduardo Akifumi Ono, Elizabeth Gusmão. Tolerance to temperature, pH, ammonia and nitrite in cardinal tetra, Paracheirodon axelrodi, an amazonian ornamental fish. Acta Amaz.vol. 38 no.4 Manaus Dec. 2008
2. Ilse Walker. The food spectrum of the cardinal - tetra (Paracheirodon axelrodi, Characidae) in its natural habitat. Acta Amaz. 34 (1): 69 - 73. 2004