There are some fish that resemble other animals such as the crocodile fish or Roosterfish, but there are also other fish that resemble certain objects such as the sawfish and the protagonist of this article: the ax fish. It has an enlarged belly in such a way that it creates an ax. There are many people who have acquired it for their aquariums and it is becoming fashionable.
In this article we will teach you all about the hatchetfish.
Key features
Freshwater axfish belong to the Gasteropelecidae family. It is about de peces from South and Central AmericaFor people who are fond of fish, this species is perfect among the best freshwater fish for aquarium. It has a deep body that is shaped like an axe. It is generally a small fish that will have a length of about 6,5 cm maximum and usually lives among 3 and 6 years depending on the care it receives and the quality of the water.
They are quite active fish if they are in a school of at least 8 or more fish. They live and feel safe in groups, so keeping them alone increases stress and makes them more susceptible to disease. They are white with a silvery appearance and, in varieties such as Carnegiella strigata (marble hatchetfish), They show greenish, yellowish, pinkish and silvery patterns with dark lines tracing their bodies. Many varieties have a horizontal black line running across their entire body. Their mouths are located on the top of their heads, allowing them to feed at the surface.
It is a species that is often confused with other ax fish of other varieties. The common hatchetfish is somewhat difficult to care for., but it becomes quite a challenge for the more experienced. In addition to the well-known Carnegiella strigata, in aquaristics it is common to see Gasteropelecus sternicla (silver hatchetfish), which is distinguished by present adipose fin (absent in Carnegiella) and a more silvery appearance. It should not be confused with the so-called marine "hatchetfishes" of the Sternoptychidae family (deep water), which are completely different species and not suitable for freshwater home aquariums.
Their natural habitat is in South America, in Brazil and in the areas where the southernmost tributaries of the Amazon are located, as well as basins in Venezuela and Paraguay. They usually inhabit the areas with slow-moving waters and banks with lots of vegetation, like quiet rivers and streams. They prefer abundant vegetation, as they can hide among it and feel protected. It usually spends most of its time near the surface.They will only move away when threatened or when actively feeding. They can sometimes be seen leaving the water to hunt flying insects, propelling themselves forward with their large pectoral fins like wings.
Meals
They are surface-dwelling carnivores. Their mouths are located on the upper part of their bodies and are used for feeding at the surface. They do not usually eat food that has fallen to the bottom, as they don't detect it well and show little interest. They feed on prey that falls to the surface of the water, such as insects, larvae, and tiny crustaceans.
The food they chase is that which is above them; does not descend to the lower strata of the aquarium to capture prey. In the wild, it captures fruit flies, mosquito larvae, and almost any food found on the surface of the water. In aquariums, it accepts small, floating live and frozen foods: fruit flies, mosquito larvae, daphnia, brine shrimp and microworms. Over time, they can accept quality floating pellets and flakes, but it's best to combine them with live or freeze-dried prey to stimulate their instinct.
If we want to have it in an aquarium, we must take into account that it will only eat food that is superior to it and that They will not survive on flake food alone if it sinks quickly. The key is to offer small particles that stay on the surface long enough. A useful trick is cut off the filtration for a few minutes at the time of feeding to prevent the current from sinking the food.
You have to provide him with a balanced diet Variety-based: Alternate high-quality live, frozen, and dried foods. For example, mosquito larvae and fruit flies, as well as some live bloodworms or brine shrimp, provide healthy protein. It's not necessary to feed them daily: 2-4 small meals a day prevent binge eating and improve activity. You can also occasionally include freeze-dried microgreens or fine plant-based foods, as some populations supplement their diet with plant matter from nature.
Behavior of the ax fish
If we are going to have it in community aquariums with other species de peces, you have to keep in mind that it will be a relatively shy and nervous fish. This is why it is necessary to place them with other fish. calm and peaceful behavior. Any more aggressive fish variety is not recommended. If you keep them with more active species, We should put a school of at least 8 or more hatchet fish so that they feel safe and reduce stress.
If we keep them in schools, they'll adapt more quickly to life in captivity. Also, as we mentioned before, they'll become more active fish, resulting in longer lives. The best fish to keep them with are small tetras. corydoras and small loricariids. Avoid large crustaceans and larger fish that may see them as preyA useful tip is to introduce the small species first and, after a few days, add the larger ones to minimize stress and negative interactions.
It's a crepuscular-nocturnal fish that likes to leap out of the water. Sometimes it can be seen motionless beneath the surface of the aquarium. This is an adaptation derived from its natural habitat, where it stays there so it can leap and "fly" through the air to hunt flying insects or escape predators. It can glide more than a meter propelled by powerful pectoral fins, a tight-fitting lid is not optional: it's a must.
Another aspect of coexistence: although sometimes certain schools can "merge", it is not advisable mix several gregarious surface species that compete for the same space if the aquarium volume isn't sufficient. This reduces conflicts and allows each group to maintain a stable hierarchy without stress.
Necessary care
They are becoming a really famous species in the aquarium world since their care is relatively easy. They are animals that, once acclimatized, will always remain healthy. The water must be kept clean and the aquarium system must be closed with a tight-fitting lid to prevent leakage. Regardless of the size of the aquarium, it must be maintained and cleaned frequently. It's quite normal for the organic matter present in the aquarium to decompose and begin to pollute the environment.
It is somewhat more sensitive to this type of situation. You also have to take into account the hardness of the water. The water must be changed regularly to maintain good conditions. At least 25-50% of the aquarium water should be replaced every two weeks., adjusting the frequency weekly if the biological load is high. This way, the acclimatization process and long-term health are more positive, maintaining low nitrates, to those who are sensitive.
They are fairly disease-resistant fish as long as the aquarium has sufficient volume. For a stable group of 8-10 individuals, it is recommended a realistic minimum of 100 liters and length of at least 80 cm so that they have a swimming surface. In small setups, a small group in 60 liters can thrive with good maintenance, although it is not ideal. Decorate the aquarium with floating plants and numerous aquarium plants forming shelters, and values a dark substrate so that they feel more secure.
It is recommended that the tank be tightly sealed so that the fish does not fall out if it jumps out instinctively. The water conditions should be soft and slightly acidic so they can thrive. Peat filtration is recommended if your water is hard, and a smooth current without turbulence that doesn't drag food from the surface. As for the substrate and lighting, they can be normal to moderate, with shaded areas created by floating plants or branches. The ideal temperature ranges between 23 and 27 ºC, with a preferred pH of 6,5-7,2 (tolerate 6-7,5) and low to medium general hardness.
Compatibility and tank mates
Peaceful and surface species, ideal for community aquariums with calm companions such as the neon fishThey work especially well with small tetras, peaceful dwarf cichlids, small loricariids, and corydoras, which occupy other strata of the aquarium. Avoid medium- to large-sized crustaceans and dominant or sized fish that can prey on or intimidate.
Because of their tendency to be shy, it's advisable to have abundant vegetation and shelter in the aquarium. Maintaining the group is essential. sine qua non for your well-beingSolitary individuals become stressed quickly and are more prone to illness. Remember not to mix several gregarious species living in the same area of the aquarium if the volume doesn't allow it.
Reproduction in aquarium
Although not always easy, hatchetfish reproduction is possible under the right conditions. In nature, it synchronizes with the start of the rainy season, so in aquariums it helps. simulate softer, slightly cooler waters, with filtration through peat and dense floating plants that offer protection. Maintain at least 6-8 copies mature increases the chances.
When mature, the male courts by waving his pectoral fins in front of the female. This will laying scattered eggs near the surface while the male fertilizes them. If breeding occurs in a community aquarium, it is advisable separate the parents after laying to prevent them from devouring eggs or fry. Another option is to use a specific breeding aquarium with mesh or dense plants so that the eggs fall out of reach.
Incubation usually lasts about 30-36 horas, depending on the temperature. From the fourth or fifth day onwards the fry swim freely and should be fed with infusoria during the first days, then moving on to brine shrimp nauplii and high-quality powdered micronutrients. Keep the water very stable, with minimal surface movement and small, frequent water changes.
Diseases and precautions
The hatchetfish is hardy if provided with a stable environment, but is susceptible to white spot (Ich) and opportunistic infections when it suffers stress from transportation or poor water quality. To prevent problems, it is key quarantine for newcomers, maintain parameters within range and provide a varied and nutritious diet.
Before any treatment, remember your preference for soft water and the fact that breathe near the surfaceAvoid medications that significantly affect surface tension or reduce available oxygen. Watch for signs of stress (gasping, loss of color, chasing) and correct the cause: increase plant cover, adjust the filter flow rate, or increase the number of individuals in the school.
I hope that these tips help you enjoy the hatchet fish.
The hatchetfish, with its distinctive hatchet-shaped body and surface acrobatics, is a great candidate for well-planted, securely covered aquariums. With a large schoola whirlpool bath, varied surface feeding and an aquarium of soft and calm water, you will be able to observe their natural behavior and, with some experience, even attempt to breed them in specific aquariums.
