Breeding aquarium fish (general)
For breeding fish in an aquarium, you need to have the appropriate knowledge – an aquarist must be able to distinguish between the sex and be able to recreate natural conditions that stimulate spawning.
Each species of fish is characterized by its own breeding method, behavior, and attitude to the offspring.
When starting to breed, an amateur must be sure that he can provide:
• healthy, grown in optimal conditions with specific characteristics of the species (body shape, size, pattern) of fish. It is safer to acquire young fish and grow independently (some authors recommend at the lower limit of the optimum temperature);
• the required number of males and females that are not hostile to each other.
When it is difficult to determine the sex of the fish, then you need to have a group of fish (usually 6-8 copies are enough);
• in some cases, 2 aquarium, 1 for males and 1 for females. In some species of fish, males and females should be kept separately for 1-2 weeks before planting for spawning. In addition, if the parameters of the water in the spawning aquarium are very different from the parameters of the water that contains fish (dH more than 5 °, the pH in the transition from more acidic water more than 0.3, from more alkaline – more than 0, 5), in these aquariums water is made with intermediate values of the specified parameters;
• enhanced fish nutrition for 2 weeks before planting for spawning, preferably with natural food;
• a glass or plexiglass spawning aquarium, preferably a length equal to 8 fish lengths and more, although there are many cases of successful spawning in smaller aquariums. Spawning aquarium before planting fish is disinfected and installed in the most peaceful and quiet place of the room (in the absence of soil on a dark colored substrate), supplied with necessary technical means, filled with the substrate and fresh water of the required parameters, the temperature is gradually adjusted to the desired parameters after landing.
Successful spawning is often helped by adding a small amount of water from an aquarium in which fish have spawned.
• a glass or plexiglass incubator is usually of a small volume (up to 20 liters) with a low water level (7-10 cm), without soil, with the same conditions of sterility and parameters as in the spawning aquarium. A disinfectant is added to the water to protect the eggs from bacteria and fungus.
The transfer of eggs to the incubator is possible by air for 10–15 s, avoiding a temperature drop.
Caviar regularly inspect and remove dead whitened eggs.
When the fry swim, start feeding them;
• starter feed for fry;
• a sterile nursery aquarium, as a rule, without soil, with a small number of plants and water rich in oxygen, usually up to 20 cm high and with a volume of 80 liters. The water parameters are at first the same as in the incubator, but then they are gradually changed to optimal for the content of this species of fish. When transferring the fry from the incubator to the nursery aquarium, they are caught not with a net, but with some kind of glass or plastic container or, to drain some of the water from the incubator, immerse it in the nursery aquarium;
For a number of fish species, you can do without the aquariums described, as they spawn in an aquarium in which they are kept, and do not pursue caviar and fry, and some species care for their offspring.
In addition, a spawning aquarium can play the role of an incubator after removing adult fish from it.
The breeding method depends on the breeding method of the fish. (according to G. Axelrod and W. Vorderuinkler):
Fish whose eggs stick to plants and other objects fall to the bottom or float in water, and fish leave it unattended
These fish are represented by the following genera: agamiks, akantofalmus, anabas, apteronotus, afiosemion (species), ayrah, lsv, ayrax, arabia, grapes, berries, food leocaspheus, macrogatus , epiplatis.
Spawning aquarium with bushes of small-leaved plants without soil is installed on a dark colored substrate. If the caviar is non-sticky, then for fish that eat caviar, a separator net is placed on the bottom.
Lighting is usually weak. The water level is usually low.
Species that spawn at one time with a large portion and eat it, during spawning, pay little attention to it and only at the end attack caviar.
In this case, help dense thickets and immediate removal of fish after spawning. Caviar shaken off the plants, collected from the bottom and transferred to an incubator.
If it is left in the spawning aquarium, which will serve as an incubator, then remove the substrate, separator grid and replace it with fresh water with the same parameters and add disinfectants.
Fish spawning in small portions over several days, usually they do not eat caviar, and they are left in the spawning tank until they receive the desired quantity of caviar or until the end of the spawning season.
Every day, the eggs are shaken off the substrate into the incubator or, after a certain period of time (for example, a week), the eggs accumulated on the substrate together with it are transferred to the incubator, and the substrate is replaced with a new one.
Caviar is desirable to carry in the water, although it is possible by air for 10-15 seconds, avoiding a temperature drop.
In the incubator, as a rule, a low level of disinfected water with the same parameters as in a spawning aquarium.
Healthy caviar is usually clear and transparent, the dead – milky, opaque, often deformed – it is removed with a pipette or sucked off with a tube. Low aeration provides oxygen and low water circulation.
Particular attention should be paid to feeding the fry and their relationship to the starter feed, which is convenient to control with a magnifying glass.
For fish that spawn, it is better to create a rest period, which is characterized by low temperature, feed restriction (1 time in 2 days) and extension of water change intervals.
Fish spawning in the ground and leaving it unattended
These fish are represented by the following genera: astrofundulus, afiosemion, notobranchius, pterolebias, zinolebias.
These are the so-called seasonal fish that live from the rainy season to the drought period. At this time, they manage to turn out from caviar, reach sexual maturity and sweep away the eggs, which wait out an unfavorable period in the soil of the dried-up reservoir.
At the bottom of the spawning aquarium lay a layer of peat and plant several bushes of plants so that the female can hide from the male. The lighting is weak, at least there should be dark areas.
The water level is not more than 25 cm. The stern of the bottom is left free.
Peat, in which fish lay their eggs, from time to time (at least every 3 weeks) is removed and replaced with new ones. It is convenient to lay on a pallet that is easy to remove from the aquarium.
The peat is placed in a net and drained of water until it drips, then it is laid in a layer of 2-3 cm and lightly dried, but it must retain enough moisture to absorb water drops and be crumbly.
Peat with caviar is stored in a closed glass or plastic container or in a plastic bag (preferably with the date of placing the peat) at a temperature of 21-23 ° C. The duration of diapause is several months.
R. Beh writes about this: “Often, different durations are due to varying oxygen content in peat of varying degrees of humidity, and it is obvious that temperature plays a certain role. Practice has shown the feasibility of storing peat at 28 ° C for the last 2-3 weeks before pouring it with water.
However, it should be kept daily only during the day for 12 hours, and at night it should be lowered to 18–20 ° C. This is the result of practical experience that has not yet found a precise explanation. “
Peat during the first 2 weeks every day inspect and remove whitened, dead eggs and do not allow them to be on the surface of the peat. Then, every week, the condition of the embryos in the roe is monitored with a magnifying glass, while at the same time checking the peat so that mold does not form.
When the embryo development is completed (the eyes are visible as dark spots), the peat is transferred to a vessel and filled with soft water with a temperature of 2-4 ° C lower than during storage.
The water level is not more than 5 cm. Then the temperature is slowly raised to 25 ° C.
The hatched fry are transferred to a nursery aquarium with the same water level, with the same parameters.
As the fry grow, the level increases and gradually changes the water parameters to the optimum for keeping this species of fish.
It happens that despite the correct development of embryos hatching does not occur. Then you need to shake the water with caviar, if it does not help, then replace the water with fresh and cold (10 ° C).
You can pour dry food (daphnia, cyclops, etc.) onto the surface of the water, which will lead to a strong development of bacteria and a decrease in the oxygen content, and the fry will tend to break through the shell of eggs to leave the unfavorable environment. They must be immediately transferred to clean water with the same parameters as in a spawning aquarium.
Caviar usually remains in peat, and it is dried, repeating the process.
Fish spawn in another organism
Gorchak ordinary (Rhodeus sericeus)
A spawning aquarium is blocked off with a low wall of plexiglass or glass at a distance of 1/4 the length of the aquarium from the side wall to ensure a drop in ground levels of pure sand of about 2-3 cm. Thickets of plants are planted on the larger, higher part of the ground snails (preferably perlovitsy, but can be toothless).
If on the next day the snails lie with wide open cusps, they have died, and they are replaced by new ones. On spawning in 10-14 days they plant a flock of fish, preferably with a predominance of females.
The pair ready for spawning is separated, and the female introduces the oviposition between the shell valves and releases about 40 eggs into the mantle cavity, which the male irrigates with milt after the female takes out the ovipositor.
Fish after spawning are removed. After 4-5 weeks, the mollusk throws out the fry that have developed and are able to swim and eat, which are transferred to a nursery aquarium.
Fish spawn on an open substrate (stone, leaf, stem, etc.) and caring for her and posterity
The following genus are presented: anomalochromis, astronotus, badis, geophagus (species), kopein, krenikara, nannakara, lamprologus, papilochromis, scalarium, discus, sturisome, tetradon, aaru, farlovela, chemichromis, cichlose, etroplus.
A spawning aquarium with a substrate that meets the requirements of the fish, soil (usually fine sand) is needed if the fish in the process of preparing for spawning pits in it or simply dig it, for some species need shelter. The lighting is moderate.
Fish of the cichl family, forming more or less constant pairs, are picky when choosing a partner, therefore it is better to purchase at least 6 copies.
Later, at the onset of puberty, a pair is formed from them, which with signs of preparation for spawning (usually the rounded belly of the female, bright color and increased aggressiveness of the male, the choice of substrate and cleaning it) are deposited in the spawning aquarium. Couple caring for caviar and offspring. In a number of species, it is not uncommon for fish to eat the first clutch of eggs, but usually this then passes.
In any case, the fish must be full and not disturbed.
There are clashes between fish because of the right to take care of the offspring, then one of them is removed. If there is only one pair in the aquarium, the male can score a female he doesn’t like to die.
You can try to separate them with a transparent partition, and when the female has a rounded belly, remove it, but in this case, success is not guaranteed.
A number of species of fish form a pair only for the period of spawning, and care for the offspring is produced either by both partners, or one of them, in the latter case the other fish is removed from the aquarium.
Delayed eggs can be transferred to the incubator together with the substrate (if by air, then for no more than 15 s, avoiding a temperature drop). A sprinkler is placed near the roe and a weak stream of air is directed so that the water moves around the roe, but the bubbles do not fall on it.
Particular attention should be paid to feeding the fry and their relation to the starter feed, which is convenient to control with a magnifier.
Fish spawn at the lower side of leaves hanging above the water
Spawning aquarium with several bushes of plants, tightly closed with a cover glass so that fish do not jump out, located at a height of 4-7 cm above the water surface. On the glass, you can stick a strip of frosted glass of green color, imitating a leaf of a plant.
For spawning is better to plant a group of fish with a predominance of females. A pair during the jump spawns on the glass, and the male takes care of it, splashing water with the blows of the tail fin.
Then the fry along with drops of water fall into the water, and they can be transferred to a nursery aquarium.
You can spawn with a cover glass to brush the bird’s feather into the incubator with a water level of 1 cm and weak aeration.
Fish spawning for shelter and caring for her and offspring
These fish are represented by the following genera: antsistrus, apistogramma, badis, brahigobius, bunocephalus, dzililikariya, krenikara, lamprologus, nannakara, nanochromis, lamprologus, pelvicahromis, rineloricaria, tetradon, tilapia, cylazoma, julidochromis.
Spawning aquarium with a substrate that meets the requirements of fish (caves or flower pots laid on its side, ceramic or plastic tubes, crevices in stones, etc.), plants and soil, if necessary. The substrate is placed in a dark place.
Fish, putting caviar in shelter, care for her, and, depending on the species, it makes a couple, male or female.
In a number of species, the fish caring for caviar behaves aggressively towards the partner, and it is removed.
After the fry begin to swim, some species continue to care, others stop it, and then the fry are transferred to a nursery aquarium.
The caviar can be transferred together with the substrate to an incubator with weak aeration (if by air, then for no more than 15 seconds avoiding a temperature drop).
Fishes spawning in cavities in the ground and caring for caviar and offspring
The following genera are presented: Jordanella, Lapomis, Papiliochromis and Enneacanthus.
Spawning aquarium with soil of fine sand with a layer of 5 cm, with a bush of plants, and for lepomis with a shelter for the female. The male digs a hole in the sand, in which the couple lays its eggs.
In papiliochromis, the grooming is carried out by a couple, in other species, the male, and the female can be removed.
Fish spawning in the nest (underwater construction of various objects, a nest of foam on the surface of the water) and caring for caviar and offspring
The following genera are presented: Belontia, Betta, Gasterosteus, Dinema, Coliseum, Ctenopoma, Macropod, Trichogaster, Trichopsis.
Spawning aquarium for fish that build a nest of foam, without soil, with plants (for some species fine-leaved, for others with large leaves), including floating ones. After spawning, the male takes care of the roe and the larvae, the female is removed.
After the fry swim and begin to take food, they remove the male.
A spawning aquarium for fish building a nest of plant parts is made with sandy soil and bushes of small-leaved plants. The male builds a nest on the ground with an entrance and exit where the roe is deposited, after which the female is removed.
Male caring for caviar and larvae.
Fish wearing fertilized eggs on their body
Presented race Orizias .
Spawning aquarium without soil with small-leaved shrubs and floating plants. Fertilized calf after spawning hangs from the belly of the female in the form of a bunch of grapes and, when she swims through the bushes, sticks to them.
Fish do not care for caviar, but do not touch the eggs and fry.
Fish incubating caviar in the mouth and caring for offspring
The following genera are presented: astatothilapia, aulonocara, betta (species), labeotrofeus, melanochromis, pseudocrenilabrus, pseudotrofeus, trophyus, chromidothilia, tirtokara.
Spawning aquarium with a substrate (flat rock or sand, in which the male makes a hole), and often a cave for shelter. After spawning, one of the fish (most often the female) takes the eggs in the mouth, and the fry that are able to swim and take food, which have been protected by their parents for some time, leave it.
A. Brüllmayer writes: “When breeding, you can use several methods:
one. Leave the female with caviar in the mouth in the aquarium.
Subject to the availability of a sufficient number of shelters.
2 Leave the female in the aquarium, separating it with a partition from the rest of the fish.
3 Transfer the female to a smaller aquarium.
I, on the basis of experience, consider the first method to be the most favorable.
On the 20th day, I catch a female and transplant it into an aquarium, the bottom of which is covered with large pebbles, and the flower pot on its side serves as a refuge for the female. Fry, leaving the female’s mouth, can hide among the pebbles.
If you act in 3 ways, then, catching the female with a net, you can damage the entire contents of the throat sac and remain without offspring.
After the fry leave the maternal mouth, catching the female is easy. It is difficult to catch a female with caviar, and I do it at night, illuminating the aquarium with a strong pocket lantern.
Often, the eggs of cichl fishes that incubate it in the mouth are grown artificially, taking eggs from the female’s mouth in the very first days and transferring it to a small vessel in which it is constantly washed with fresh water with the addition of a disinfectant. When taking eggs from the female, care must be taken not to damage the bones of the jaw and skull.
I believe that artificial cultivation is justified only when the success of breeding very valuable imported fish is questionable and at the same time the aquarist impeccably knows the methods of proper handling of the female. “
(This refers to the family of cichl fish)
Artificial incubation of eggs produced as follows. The female is wrapped in a soft, pre-soaked cloth so that only the mouth remains free.
Hold the fish head down and with the tip of a finger or glass spatula gently open the mouth and slowly periodically lower the fish into the water or remove it from it. As a result, it spits out eggs, which are transferred using a glass tube to an incubator with a water level of 5–8 cm and weak aeration.
Water with parameters that meet the requirements of this type of fish, and with the addition of a disinfectant, is changed at least once a day.
Incubators designed by amateurs. In them, the incoming water from the bottom throws up eggs, causing them to constantly move and rub against the walls, which prevents bacteria from settling on them.) Caviar is regularly inspected and whitened, deformed, or with droplets of fat or gas removed. After the fry swim, the water level gradually increases.
It should be noted that with artificial incubation, the fish lose the ability to incubate it independently.
Fish whose development of eggs and hatching of larvae occur in the body of the female, and it is abandoned by fully formed, able to swim and feed fry – Viviparous fish
The following genera are presented: alfaro, gambusia, girardinus, dermogenis, xenotoka, xyphohorus, pecilya.
G. Axelrod and W. Vorderinkler recommend, when the female’s body is rounded, to transfer it to a separate aquarium with abundant vegetation, incl. floating and feed well. Fry will have the opportunity to hide, and a well-fed female rarely suffers from cannibalism.
They do not recommend using the so-called “spawning traps”, since negatively affect the nervous system of the female and are dangerous for her offspring.
“Spawning trap” is a small mesh or Plexiglas with slots in the bottom of the aquarium, which is suspended in a conventional aquarium.
The female is placed in the “trap” and the fry swim through its slots or network cells into the aquarium, becoming inaccessible to the female.
More detailed breeding conditions are given when describing genera and fish species.