Common Hatchetfish - Gasteropelecus sternicla : Complete Fish Profile & Care Guide
Table of contents
Introduction
Common Hatchetfish (Gasteropelecus sternicla) are an intriguing and delicate shoaling species that boast captivating behaviour and appearance. Native to regions of South America, particularly the Amazon River basin, these hatchetfish exhibit remarkable characteristics that make them a sought-after addition to freshwater aquariums. Their distinct body shape, resembling that of a hatchet, lends them their name and sets them apart in the aquatic realm. In the wild, Common Hatchetfish are known to gather in sizeable numbers, underscoring their social nature and preference for companionship.
In the aquarium setting, it is essential to maintain these hatchetfish in groups of 6 or more, with larger groups of 10 or more being optimal. This social arrangement provides them with a sense of security and allows them to exhibit their natural behaviours comfortably. When selecting tank mates, it is crucial to opt for small and peaceful species, as Common Hatchetfish are easily susceptible to intimidation. Consider companions such as peaceful Tetras, Pencilfish, Corydoras Catfish, and Dwarf Cichlids like Apistogramma or Mikrogeophagus. Additionally, smaller suckermouth Catfish can be suitable companions in a well-thought-out community setup.
Creating a conducive environment for Common Hatchetfish necessitates a mature and efficiently filtered aquarium. While maintaining gentle water movement, the addition of peat to the filter can aid in achieving soft and slightly acidic water conditions, mimicking their natural habitat. A carefully curated decor scheme involving dark elements, ample bogwood, strategically placed caves, and a mix of well-chosen plants, including floating species, will enhance their comfort and security.
Given their propensity for leaping, it is imperative to equip the tank with a tightly fitting lid to prevent any potential escape attempts. Furthermore, meticulous attention to water quality is essential, as Common Hatchetfish can be sensitive to fluctuations in water chemistry and elevated nitrate levels. By adhering to these considerations and creating an environment reminiscent of their native habitats, aquarists can enjoy the captivating presence and behaviours of this remarkable hatchetfish.
Common Hatchetfish have deep, white or silvery bodies with a prominent, black horizontal line running through the centre of their body. Their mouth is situated close to the top of their head, enabling feeding at the surface. The most striking feature of the Common Hatchetfish is their large, wing-like pectoral fins that propel them out of the water when startled. It is recommended to have a tight-fitting lid on the aquarium since they are known to jump, especially when catching small flying insects. Despite their small size, these fish are easily recognisable by their protruding bellies, which resemble hatchets.
Common Hatchetfish Photos
Sexual Dimorphism
Differentiating between male and female Common Hatchetfish (Gasteropelecus sternicla) is indeed a challenging task. When viewed from above, the females are slightly larger and have a rounder body, particularly when gravid (carrying eggs). This subtle difference in size and body shape may not always be noticeable until the females are ready to spawn, making sexing these fish difficult for aquarists.
Due to the nuanced physical differences and the absence of distinct sexual dimorphism common in many fish species, identifying males and females within a group of Common Hatchetfish can require close and careful observation over time. Aquarists interested in attempting to sex their hatchetfish should pay particular attention to their fish during feeding or when the fish exhibit spawning behavior, as these times may offer the best opportunity to discern the slight variations in body shape and size indicative of each sex.
Given these challenges, aquarists often rely on group dynamics and behavior rather than physical characteristics alone to infer the presence of both sexes in a group, especially when aiming to encourage natural spawning conditions within their aquariums.
Quick Facts
| Scientific Name | Gasteropelecus sternicla |
|---|---|
| Year Described | 1758 |
| Other Names | River Hatchetfish |
| Kingdom | Animalia |
| Classification | Actinopterygii |
| Order | Characiformes |
| Family | Gasteropelecidae |
| Genus | Gasteropelecus |
| Origins | Guyana , Suriname , Peru |
| Max Size | 6.5 cm |
| Temperament | Peaceful |
| Aquarium Level | Top |
| Difficulty | Beginner - Intermediate |
| Shoaling | Yes |
| Best kept as | Groups 6+ |
| Diet & Feeding | Omnivore |
| Reproduction | Egg-Scatterer |
| Average Lifespan | Up to 5 Years |
Water Parameters
| Water Type | Freshwater |
|---|---|
| pH | 6.0 - 7.0 |
| GH | 2 - 15 |
| TDS | 18 -215 |
| ℉ | 73 - 81 |
|---|---|
| ℃ | 22 - 27 |
Natural Habitat
In their natural habitat, Common Hatchetfish (Gasteropelecus sternicla) thrives in slow-moving waters, such as small streams, rivers, and swamps, that are densely populated with surface vegetation. These fish can be found in various regions of South America, including Guyana, Suriname, Peru, Venezuela, and Brazil's Rio Paraguay Basin.
Breeding
Despite their popularity in the aquarium trade, successful captive breeding of the Common Hatchetfish (Gasteropelecus sternicla) remains a challenge. Consequently, there are no established guidelines or documented reports available for hobbyists interested in breeding this species in a captive environment. This situation underscores the difficulty in replicating the precise conditions required for their spawning and development within an aquarium setting.
Efforts to breed Common Hatchetfish should focus on closely mimicking their natural habitat conditions as much as possible. This includes maintaining soft, slightly acidic water within the appropriate temperature range, providing a diet rich in live foods to condition the adults for breeding, and ensuring the presence of floating plants or similar structures to serve as potential spawning sites. Additionally, keeping a well-covered aquarium is crucial to prevent the fish from jumping out, especially since hatchetfish are prone to leaping from the water.
Given the lack of specific breeding information for Gasteropelecus sternicla, hobbyists may need to experiment with different conditions and setups, drawing on general practices known to encourage breeding in similar tropical fish species. Observation of any breeding behavior, such as increased activity or chasing, may provide clues for further adjustments to the breeding environment.
Ultimately, the successful breeding of Common Hatchetfish in home aquariums would not only be a significant achievement for the hobbyist but also contribute valuable insights into the care and propagation of this enchanting species. Hobbyists are encouraged to share their experiences and findings with the aquarium community to help advance collective knowledge on the subject.
Diet & Feeding
In their natural habitat, Common Hatchetfish (Gasteropelecus sternicla) primarily consume a carnivorous diet consisting of worms, insects, and crustaceans. However, in the aquarium environment, they can readily adapt to eating prepared foods, with micro pellets being one of the best options as they can provide the necessary nutritional requirements for these fish. If initially hesitant to consume prepared foods, offering a mixture of frozen or live foods during feedings can help acclimate them to this new diet.
While it may take some time for them to adjust, Common Hatchetfish should eventually accept prepared foods. Given their carnivorous nature, it's essential to include regular feedings of live or frozen foods in their diet to ensure optimal health and nutrition. Excellent live food options for Common Hatchetfish include mosquito larvae, blackworms, wingless fruit flies, and daphnia. Similarly, frozen foods such as bloodworms, brine shrimp, daphnia, and blackworms are all highly nutritious options that can supplement their diet effectively in captivity.
