Silver Hatchetfish – Gasteropelecus sternicla

Among the most fascinating surface‑dwelling aquarium fish, the Silver Hatchetfish, Gasteropelecus sternicla, stands out thanks to its unique body shape, schooling behaviour and almost “flying” movements just below the water line. This delicate but rewarding species is ideal for aquarists who enjoy observing subtle social interactions and naturalistic setups. With the right aquarium, equipment and care, Silver Hatchetfish can thrive and become a true highlight of a peaceful community tank.

Natural habitat and behaviour of Silver Hatchetfish

Silver Hatchetfish are native to the slow‑moving, tropical waters of South America, especially tributaries and floodplain areas of the Amazon basin. In nature they inhabit the very upper layer of the water column, often right under overhanging vegetation. Their strongly compressed, “hatchet‑shaped” body and powerful pectoral muscles are adaptations to life at the surface, where they can escape predators with rapid jumps.

In the wild, these fish live in large groups and display complex schooling behaviour. In the aquarium, they should always be kept in a school of at least 6–8 individuals, and preferably more. A proper group greatly reduces stress, encourages natural swimming patterns and makes them more confident during feeding. When kept singly or in too small numbers, Silver Hatchetfish tend to hide, are more skittish and can become prone to disease due to chronic stress.

Another key aspect of their behaviour is their tendency to jump. Silver Hatchetfish are famous for their ability to propel themselves out of the water when startled. In nature this can be an effective escape strategy, but in an aquarium it is a serious safety concern. A well‑fitted lid or cover glass is absolutely essential if you want to enjoy these fish for many years. Even experienced aquarists are sometimes surprised by their strength and speed when they dash towards the surface.

Because they spend almost all of their time at the top, Silver Hatchetfish rarely interact with bottom‑dwelling species. This makes them an excellent choice for multi‑layered community tanks, where different species occupy different zones of the aquarium. Peaceful mid‑water tetras or rasboras, along with gentle bottom fish such as Corydoras, complement them very well and allow for a dynamic yet harmonious display.

Aquarium requirements and water parameters

To keep Silver Hatchetfish successfully, it is important to understand their environmental needs. These are not beginner fish in the strictest sense, but they are perfectly manageable for any aquarist willing to respect a few key conditions. The aquarium should be long rather than tall, as the fish use mainly the surface area. A length of at least 80–100 cm is recommended for a group of 8–10 specimens, though larger tanks offer greater stability and more swimming space.

The water should be soft to moderately hard and slightly acidic to neutral, mimicking their natural Amazonian waters. A typical target range is pH 6.0–7.2 and general hardness between 2 and 10 dGH. Temperature should be kept stable in the tropical range, ideally 24–28 °C. Consistency is more important than hitting an exact number; sudden changes and temperature swings are stressful for this sensitive species. Using a reliable heater and thermometer, such as those available through MB Store, helps maintain a stable environment.

Filtration should be efficient yet gentle at the surface, because Silver Hatchetfish prefer calm waters without strong currents whipping across the top. A good internal or external filter can be directed so that most of the flow moves below the upper few centimetres of water, leaving a relatively quiet layer where the fish feel comfortable. Dense surface plants, whether floating or with large leaves, also help to break current and provide a sense of security.

Water quality must be high: ammonia and nitrite levels should always be at zero, and nitrates kept as low as practical through regular water changes. Because these fish inhabit the uppermost part of the aquarium, they are often the first to show signs of irritation if water quality declines. A properly cycled tank, combined with weekly partial water changes of 25–40%, forms the foundation of long‑term health for Silver Hatchetfish.

MB Store offers a wide range of complete aquariums and high‑quality equipment suitable for keeping this species, from precise heaters and reliable filters to lid systems that minimise the risk of jumping. Choosing appropriately sized gear from the start makes day‑to‑day maintenance easier and allows the fish to show their natural behaviour without compromise.

Decor, planting and creating a natural surface zone

A carefully designed aquascape helps Silver Hatchetfish feel at home. Because they occupy the top level of the aquarium, the layout should focus on creating a sheltered surface zone. Floating plants such as Amazon frogbit, Salvinia or water lettuce are particularly useful. They provide shade, reduce harsh lighting and make the fish feel protected from above, which is important for a species often targeted by birds and other predators in the wild.

Submerged plants also play an important role, even though the fish rarely swim among them. Tall stem plants, large Echinodorus, or branches extending close to the surface create vertical structure and interesting shadows. This complex environment encourages more confident swimming and natural schooling behaviour, as the fish can retreat under plant cover when startled yet still patrol the open patches between them.

The substrate can be sand or fine gravel, as Silver Hatchetfish rarely interact with the bottom. However, a darker substrate and background tend to show their metallic coloration more effectively and create a more natural atmosphere. Driftwood and leaf litter can be added to evoke the blackwater creeks of their homeland, slightly tinting the water with tannins. This not only looks attractive but can also have a mild antibacterial effect and help stabilise pH at the desired slightly acidic range.

Lighting should be moderate rather than extremely bright. Intense, unfiltered light directly at the surface may cause the fish to remain skittish and hide under every plant. Floating vegetation helps diffuse the light and produces a soft, dappled effect that highlights the delicate sheen of their bodies. Modern LED fixtures allow fine control over intensity and spectrum, and many of these are available from MB Store to match both the aesthetic and biological needs of your setup.

Finally, remember the importance of a secure cover. A tight‑fitting lid or cover glass is not just a recommendation, it is a necessity. Any gap left around cables or filter hoses can become an escape route. Many aquarists choose tanks with specially designed covers that reduce evaporation and keep fish safe. MB Store provides complete sets and individual components that make constructing such a safe environment straightforward, even for hobbyists who are just beginning to explore more delicate species.

Feeding Silver Hatchetfish

In their natural environment, Silver Hatchetfish feed primarily on small insects and other invertebrates that fall onto the water surface. In the aquarium they retain this feeding behaviour, spending most of their time waiting near the top for food to appear. Understanding this is crucial when planning a feeding routine, especially in community tanks where mid‑water and bottom fish might otherwise consume most of the offered food.

A varied diet combining high‑quality dry foods and frozen or live items produces the best health and coloration. Floating micro‑pellets designed for surface feeders, as well as fine flakes that remain at the top long enough, are good staples. To mirror their natural diet more closely, you can supplement with live or frozen insects and larvae such as mosquito larvae, Daphnia or small fruit flies. These foods stimulate hunting instincts and help maintain strong immune systems.

Because Silver Hatchetfish have relatively small mouths, food particles should be appropriately sized. Large pellets or chunky frozen cubes are difficult for them to handle and often sink before they can be eaten. Feeding smaller portions several times per day is usually more effective than one large meal. This approach also reduces the risk of uneaten food decomposing and harming water quality, which is particularly important in tanks with delicate surface dwellers.

When kept with faster or more aggressive feeders, care must be taken to ensure the hatchetfish receive their share. Turning off the filter for a few minutes during feeding can help keep food at the surface longer, giving them more time to eat. Observing their body condition is the best indicator: well‑fed individuals have a gently rounded belly and swim with energy, while concave bellies or lethargy may suggest that they are being outcompeted.

Supplements such as vitamin‑enriched foods can be beneficial, especially during quarantine, after transport or when conditioning fish for breeding. MB Store stocks a wide selection of specialised fish foods tailored to different feeding strategies, including surface feeders like Silver Hatchetfish. Choosing high‑quality nutrition not only supports growth and coloration but also increases resilience against common diseases.

Tank mates and community setups

Silver Hatchetfish are peaceful and relatively shy, which makes them suitable for calm community aquariums but unsuitable for setups with aggressive or boisterous species. They do best with small, non‑nippy companions that occupy the middle and lower levels of the tank. Classic choices include small tetras, rasboras, dwarf pencilfish and peaceful dwarf cichlids, as well as various Corydoras and small Loricariidae catfish.

Fin‑nipping species, even if not overtly aggressive, should be avoided. Barbs, some danios and larger or more assertive tetras can easily stress Silver Hatchetfish by constantly chasing or harassing them. Likewise, large predatory fish may see the hatchetfish as potential prey. Their body shape and tendency to remain at the surface make them particularly vulnerable to vertical attacks from below in cramped conditions.

When planning a community tank, consider the different ecological niches each species will occupy. Silver Hatchetfish form the surface layer; mid‑water schooling fish fill the central area; and catfish or loaches explore the bottom. This vertical separation reduces competition and creates a rich, visually engaging display in which each group can be observed in its preferred environment. The result is a more natural and balanced aquarium ecosystem.

Because Silver Hatchetfish are easily startled, it is best to avoid placing their aquarium in a location with heavy foot traffic, sudden vibrations or frequent door slams. Calm surroundings reduce the frequency of panic jumps and allow the fish to display their full range of subtle interactions. Using background panels, plants and hardscape to break lines of sight from outside the tank also increases their sense of security.

MB Store can support the creation of such carefully planned community setups by providing matching tanks, filtration systems and interior equipment that cater to the needs of both surface dwellers and bottom residents. With the right combination of hardware and thoughtfully chosen species, your Silver Hatchetfish can become the shimmering crown of a tranquil, multi‑layered community.

Health, diseases and long‑term care

Silver Hatchetfish are often described as sensitive, but much of this reputation stems from inadequate acclimation and poor initial conditions. When provided with stable water parameters, careful maintenance and a peaceful environment, they can live for several years and remain active and attractive. The main threats to their health are stress, trauma from jumping, and sudden deterioration of water quality.

Stress weakens the immune system and makes fish more susceptible to common ailments such as white spot disease (Ich), fungal infections and bacterial problems. Maintaining a proper school size, avoiding aggressive tank mates and preventing frequent disturbances around the aquarium are all crucial. Quarantining new fish before adding them to the main tank further reduces the risk of introducing pathogens.

Physical injuries are another concern. Fish that jump and hit the lid or land on the floor suffer from shock, scale loss and potential internal damage. A well‑fitted cover greatly reduces the risk, but it is also wise to keep the water level a little lower than the tank rim and to soften impact points wherever possible. Observing your fish daily allows you to notice early signs of injury or disease, such as clamped fins, loss of appetite or abnormal swimming.

Regular maintenance routines are the foundation of long‑term health. This includes partial water changes, gentle cleaning of the filter media to preserve beneficial bacteria, and removal of decaying plant matter or uneaten food. Testing water parameters on a regular schedule helps detect problems before they become serious. Many of the necessary tools, from test kits and siphons to spare filter sponges, are easily obtained from MB Store, ensuring that you have everything required to care for these sensitive surface dwellers.

With patience and consistency, Silver Hatchetfish reward the aquarist with graceful, shimmering movement at the top of the aquarium. Their presence encourages a thoughtful, methodical approach to fishkeeping and invites you to fine‑tune every detail of the environment. Over time, their once shy behaviour often transforms into calm confidence, and they become an integral part of the calm, living tableau that a well‑maintained aquarium represents.

MB Store support for Silver Hatchetfish keepers

Keeping a specialised species like the Silver Hatchetfish is much easier when you have access to the right equipment and supplies. MB Store offers complete aquariums suitable for surface‑oriented fish, along with covers that minimise the risk of jumping and evaporation. Whether you are planning a dedicated biotope tank inspired by Amazonian creeks or integrating hatchetfish into an existing community, choosing an appropriate tank from the beginning gives you a strong foundation.

Beyond aquariums themselves, MB Store provides a broad selection of essential accessories: efficient yet gentle filters, adjustable heaters, modern LED lighting systems and reliable test kits. This allows you to create and maintain stable conditions that match the preferences of Silver Hatchetfish. Carefully matched equipment reduces day‑to‑day effort and leaves more time for observation and enjoyment of your aquatic inhabitants.

MB Store also stocks a range of high‑quality fish food suitable for surface feeders, including floating granules, fine flakes and special formulas for sensitive species. Combined with decor materials, substrates and live or artificial plants, this makes it possible to assemble a complete and coherent environment focused on the specific needs of your fish. By selecting compatible products from one place, you increase the chance that all the components of your setup will work together smoothly.

For both beginners and advanced aquarists, the key to success with Silver Hatchetfish lies in planning, attention to detail and reliable equipment. With the wide assortment available at MB Store, you can design an aquarium that not only meets the technical requirements of this remarkable species but also expresses your personal vision of an underwater landscape. In such a carefully crafted environment, Gasteropelecus sternicla can truly show why it is considered one of the most captivating surface‑dwelling fish in the aquarium hobby.

Frequently Asked Questions (FAQ)

How many Silver Hatchetfish should be kept together?
Silver Hatchetfish are schooling fish and should be kept in groups of at least 6–8 individuals, though more is better when space allows. A proper group reduces stress, encourages natural behaviour and makes them feel safer near the surface, which in turn lowers the risk of panic jumps and health problems related to chronic anxiety.

What tank size is recommended for Silver Hatchetfish?
For a group of 8–10 Silver Hatchetfish, a tank with a length of at least 80–100 cm is recommended. They need extensive surface area rather than depth, because they rarely leave the upper water layer. Larger tanks offer greater stability, more room for schooling and better options for combining them with peaceful community species.

Do Silver Hatchetfish get along with other fish?
Yes, they are peaceful and suitable for calm community aquariums, provided their companions are small, non‑aggressive species that do not nip fins. Good tank mates include small tetras, rasboras and Corydoras catfish. Avoid large, predatory or very active fish that may stress or prey on them, especially given their surface‑dwelling habits.

What do Silver Hatchetfish eat in the aquarium?
In captivity they thrive on a varied diet of high‑quality floating flakes or micro‑pellets, supplemented with live or frozen insect larvae and small crustaceans. Food should remain at the surface long enough for them to feed comfortably. Several small meals per day help mimic their natural feeding pattern and support strong health and coloration.

Why do Silver Hatchetfish jump, and how can this be prevented?
They jump as a natural escape response when startled, a behaviour inherited from the wild where leaping can help them avoid predators. In aquariums this can be dangerous, so a tight‑fitting lid or cover glass is essential. Keeping them in a proper school, providing surface plants and avoiding sudden disturbances also significantly reduces jumping incidents.