The Silver Hatchetfish, also known as Gasteropelecus levis, is one of the most popular pet trade species.

With their unusual body shape and metallic sheen, they are sure to provide endless fascination to their spectators. However, they are not the easiest fish to have.

To make sure you won’t run into problems, you need to understand their care requirements.

Silver Hatchetfish Stats

Category Rating
Scientific Name Gasteropelecus levi
Family Gasteropelecidae
Genus Gasteropelecus
Care Level Difficult
Temperament Peaceful, skittish
Compatibility Non-aggressive mid- and bottom-dwellers
Average Size 1.5 inches
Color & Patterns Silver
Diet Carnivore
Min. Tank Size 30 gallons
Tank Setup Subdued lighting

Floating plants

Dark-colored substrate

pH 5 – 7
Temperature 74⁰ – 83⁰ F

Where Do They Originate?

The Silver Hatchetfish is a schooling fish native to the jungle streams in the Amazon Basin’s southernmost reaches. Scientifically known as Gasteropelecus levis, it is one of the famous big-bellied quartets of the genus Gasteropelecus.

During the rainy season, the fish also make their way into the flooded forests. Their species can also be found in the lower sections of the Guamá River and the Tocantins River.

What Makes Them Unique?

The freshwater Silver Hatchetfish earned its name because of its reflective silver color and enormous sternal region, closely resembling an ax’s head. However, there is more to this fish than its bulbous belly.

Do Silver Hatchetfish Fly?

Yes! It may surprise you, but the Silver Hatchetfish can fly. Adding to that, hatchetfish are the only fish that can perform an actual powered flight. The pronounced barrel chest harbors strong muscles, and side fins are huge and elongated. Up to 25% of the fish’s weight comprises pectoral muscles. The bulbous-belly also serves as a keel for the fish. Albeit odd-looking, this structure is all a part of an efficient flying mechanism that allows hatchets to prey on insects or flee from danger.

Initially, they would leap out of the water by pressing their pectoral fins downwards. And like a young bird learning to fly, they make rapid beats of their large pectoral fins to sustain powered flight for a short period. Due to a large amount of energy required to jump and fly, the fish can only repeat this behavior once or twice.

Do Silver Hatchetfish Reflect Light?

Yup. One moment they would like sparkling stars. The next moment you get flash bombed.

The Silver Hatchetfish can manipulate light makes them all the more interesting to have in a home aquarium. When you have a big group of Silver hatchetfish, their aluminum-like skin reflects the LED light above when they shoal together and make sharp turns.

Silver Hatchetfish vs. Common Hatchetfish: What Makes Them Different?

People often mistake the Gasteropelecus sternicla for the Gasteropelecus levis, although they are two different species under the genera Gasteropelecus. To add the confusion, some suppliers are selling both species as the “Silver Hatchetfish.” The truth of the matter is the G. sternicla is what experts call the “Common Hatchetfish.” Not the other way around.

While the Silver Hatchetfish and Common Hatchetfish may look similar, they exhibit certain behaviors not seen in other hatchet species. The G. sternicla prefers to stalk its prey rather than pursue it. But when it comes to feeding times, the gluttonous Common Hatchetfish will most likely out-compete its tankmates.

At 3.5 inches, the Common Hatchetfish is also larger than the Silver Hatchetfish. The silver hatchetfish size, on the other hand, maxes at 1.5 inches.

Silver Hatchetfish Care: Are They Difficult?

Unfortunately, yes. The Silver hatchetfish lifespan is three years, but these species seldom exceed two years in captivity. Silver hatchets have a reputation for being difficult to keep alive, given their behavior. Thus, you will need to understand what these peculiarities are to prevent problems in the future.

Silver Hatchetfish Diet

Silver hatchets are not as bashful as they typically are when it comes to food. They are quite the sight when feeding.

In the wild, the freshwater Silver Hatchetfish feed on live aquatic insects and larvae, crustaceans, and worms. The devout carnivores would dart toward their prey and gobble them up with gusto. Vegetable components do not factor into their natural diet. That said, you will need to replicate this dietary regimen as closely as possible to keep them in tiptop condition.

Here is a list of food to make your Silver hatchets happy:

  • Bloodworms
  • Brine shrimp
  • Flightless fruit flies
  • Daphnia
  • Pinhead crickets
  • Tubifex

You may also feed your Silver hatchets protein-rich flakes and floating pellets, although they will not appreciate them at first. It will take some time before Silver hatchets accept fish feed. So until then, a large portion of their diet should consist of frozen or live food.

And when you feed them, you need to see them eat. Silver hatchets are prone to malnutrition because most foods end up sinking into the bottom of the aquarium. A good rule of thumb is to turn off aeration and filtration during feeding times. Water turbulence can cause the floating fare to sink faster.

Moreover, it would be best if you considered what other fish to add to your tank carefully. Silver hatchets can be easily out-competed at feeding times, causing them to die of underfeeding.


The most significant difference between the Silver Hatchetfish and its cousins is their level of skittishness. Apart from being shy, Silver hatchets can be wayward and excitable to boot. They get on edge if you place the aquarium in a high-traffic area of your home.
Skirmishes may sometimes happen among them, but these are only a form of play. No harm comes of it.

As with other species, the Silver ones are also notable for making unsanctioned jumps that could lead to their untimely deaths. Although they are less prone to impulsive jumping compared to their Common and Marbled cousins, you will need a tightly covered tank nonetheless.

These fish will jump out of the tank whenever they see an insect sitting nearby. The temptation is too hard to resist. You do not want to take the chance. Floating aquatic plants can also help deter this behavior.

Silver Hatchetfish Tank Mates: Are They Territorial?

No, they are not. Marbled hatchets may exhibit intraspecies territoriality when grouped in large numbers. So, refrain from housing different Gasteropelecus species in one tank. Albeit rare, you do not want to take the chance.

Silver hatchets do not get along with Common hatchets, as well. The latter can be pretty aggressive when it comes to food. Although this aggression might be but bluff and bluster, Silver hatchets can get quickly stressed given their timid nature. This holds true, especially when they are few and outnumbered.

Therefore, you will need to keep them in groups of at least eight. The more, the merrier! These fish can only thrive when kept in a large group.

Make a Good Aquarium Resident

Silver hatchets can coexist with virtually all non-aggressive species that have the same water-condition requirements as them on the bright side. Since Silver hatchets occupy the aquarium’s upper niche, their best tankmates would be mid- and bottom-dwellers.

Tetras and cories, in particular, are fantastic companions for your Silver Hatchetfish.

  • Black Widow Tetra
  • Head and Tail Light Tetra
  • Rummy Nose Tetra
  • Silver-tipped Tetra
  • Adolfo’s Cory
  • Bandit Cory
  • Panda Cory

Silver Hatchetfish compatibility is crucial to ensure a healthy community within your aquarium. By choosing mid- and bottom-level dwellers, your Silver hatchets will not have to compete for food and space. Therefore, it prevents the stress that could otherwise compromise the health of your fish.

Moreover, it would be best if you did not keep your Silver hatchets with high-energy fish that will swim at any level, such as Zebra Danios. These boisterous fish could easily scare your Silver hatchets.

Silver Hatchetfish Breeding

Silver hatchets are known to deposit their eggs among plants, particularly those near the water surface. It is believed that temperature and natural light can affect the Silver Hatchetfish growth rate. Eggs that are exposed to sunlight would hatch within 24 hours.

But beyond that, not much is known about the breeding behavior of this species. Males and females are likewise difficult to distinguish. However, the latter would always have a rounder belly when laden with eggs.

Setting Up

Silver hatchets thrive best in a mature aquarium in which the biological processes have been long stabilized. A new setup often has water parameter fluctuations, which is bad news for your fragile pet.

Water Requirements

Your tank’s acidic and alkaline levels will drop and rise pretty regularly. Still, you need to keep the pH between 5.7 and 7.0 for your Silver Hatchets. A severe decrease or increase in pH levels will compromise the health of your fish.

Likewise, the Silver Hatchetfish are highly susceptible to stress-related ailments during ammonia spikes, even more so than other species. The fish seldom show signs of distress until it is too late. Therefore, you will need to be extra diligent when it comes to cleaning your tank. The hardness level is of slightly less importance to Silver hatchets. Regardless, you will want to keep dGH in the range of 3.0 to 17.0. Meanwhile, the acceptable silver hatchetfish temperature is between 74⁰ and 83⁰.

Plants, Lighting, and Substrate

In the wild, these fish would find refuge in dangling roots and floating vegetation. So, consider adding live floating plants for the bashful Silver Hatchetfish in your home aquarium. These fish will relish taking cover in those plants while resting. Sword-like plants whose leaves reach the waterline are also excellent options.

Since Silver hatchets live under forest canopies, you will need to subdue lighting.
Silver hatchets do not care what goes on underneath, as they only live in the tank’s upper few inches. Regardless, a dark substrate is preferable for this species, as it stimulates the river bottom. Rocks and fallen branches are great additions, as well.

A Word of Caution: The Biggest Problem When Buying Silver Hatchetfish

Premature death is the most prominent problem aquarium hobbyists often run into when getting Silver Hatchetfish, especially when it is their first time. When you see them displayed in big groups, they are likely underfed. The shop attendant has to take time to see them eat, especially since these fish are somewhat challenging to feed. Otherwise, most of the fish will end up malnourished.

If the fish are underfed, their immune systems are compromised. So, if they come into your aquarium, they may have Ich or some common disease. We recommend you quarantine them and make sure to feed them well. If the fish has Ich or bacterial infections, you can treat them accordingly and contain the disease’s spread.


The Silver Hatchetfish have been in the aquarium hobby for a long time. Aquarists have many reasons to keep them. However, caring for Silver hatchets is more than just emulating their habitat and feeding them protein-rich fare.

To ensure success, remember the following:

  • The Silver Hatchetfish do best in a school of 8 or more, especially when you add them to a large community tank.
  • These fish do not fare well with boisterous tankmates.
  • The Silver Hatchetfish diet comprises 90% insects, which you should recreate as closely as possible in captivity.
  • You must have a hood or a tight-fitting lid on your tank without large openings to deter their impulsive flying.
  • Alleviate the skittishness of the fish by adding floating plants.
  • Fluctuations in pH levels or an increase in ammonia ills your fish.
  • Quarantine newly bought Silver Hatchetfish to prevent the spread of disease.

Lastly, don’t forget that the Silver Hatchetfish is different from the Common Hatchetfish, G. sternicla. Each species has its own set of considerations. If you keep these points in mind, I am sure these South American fish will bring charm and diversity to your aquarium for a long time.

5/5 - (17 votes)


Please enter your comment!
Please enter your name here