Freshwater Hatchetfish (Gasteropelecidae)

Platinum Hatchetfish

Thoracocharax stellatus

Thoracocharax stellatus, also known as the Golden or Platinum Hatchetfish, belongs to the family Gasteropelecidae. These fish impress with their unusual body shape, making them an attractive choice for aquarists, especially beginners, due to their relative ease of care.

Tank
from 243 L (64 gal), 250 L (66 gal) recommended
Temperature
20 – 28 °C (68 – 82 °F)
Size in aquarium
6 – 7 cm (2.4 – 2.8 in)
Acidity
pH 5–7.5
Natural rangeRange on the map
  • South America area
  • Argentina
  • Bolivia
  • Brazil
  • Colombia
  • Ecuador
  • Paraguay
  • Peru
  • Uruguay
  • Venezuela

Tank conditions

Plan the tank stocking
Temperature
20 – 28 °C (68 – 82 °F)
Water pH
Slightly acidic (5) – Neutral (7.5)
Water dH
Very soft (1) – Hard (15)
Water salinity
no salt (freshwater)
Size in aquarium
6 – 7 cm (2.4 – 2.8 in)
Lifespan
5 years
Temperament
Peaceful (regular)
Toward small fish
not a predator
Required aquarium volume
from 243 L (64 gal), 250 L (66 gal) recommended
Lighting
dimmed or moderate
Substrate
any (no restrictions)
Water flow
weak or moderate
Swimming level
near the surface
Feeding
Floating (any)
Keeping
Large group 10+ individuals
Jumping
high a tight-fitting lid is essential
  • Lifespan. A lifespan to expect under good care, not a measured value: it depends heavily on tank volume, water quality and diet — and for selectively bred forms, on their origin as well.
  • Toward small fish. Based on the Predators category in the catalog or the temperament in the species parameters. “A risk to small fish” means the species is not a predator by habit, yet will swallow any fish that fits in its mouth.
  • Required aquarium volume. The 243 L minimum corresponds to a tank footprint of 120×45 см. The recommended 250 L is for the group size given under keeping mode.

Care and keeping

Description

Adult hatchetfish reach a length of about 6–7 cm. Their body has a characteristic wedge shape, strongly compressed laterally, making them resemble an axe blade. The belly of these fish is silvery, while the back is colored in yellow tones with a golden sheen. Under certain lighting, bluish stripes may appear on their body.

Habitat

The natural habitat of this species covers South America. Among all hatchetfish, it is the most widespread, found almost everywhere in major river systems such as the Amazon, Orinoco, and Paraná. Preferred habitats include stagnant waters: quiet backwaters, swamps, and floodplain lakes, where they often stay near abundant surface vegetation.

Behavior and Compatibility

This peaceful and benevolent species prefers to live in schools of its own kind or in the company of other calm fish. Good tank mates include small tetras, Corydoras and Plecostomus catfish, as well as Geophagus cichlids and Apistogramma, and many other species. There is a common misconception that these fish can perform long "flights" above the water due to their large pectoral fins resembling wings. However, research conducted in 1995 disproved this legend.

Care and Maintenance

For a comfortable group of ten hatchetfish, an aquarium of at least 250 L will be required. The aquascape can be arbitrary, but special attention should be paid to the upper water column. It is important to provide both open areas for swimming and zones with dense thickets of floating plants, which will serve as cover. The choice of other decorative elements is not critical and depends on the aquarist's preferences or the needs of other inhabitants. Long-term and successful keeping is possible with the maintenance of high water quality (low pollutant content), stable temperature, and hydrochemical parameters. Golden hatchetfish adapt well to a fairly wide range of pH and dGH values, so maintaining them at the required level will not be difficult with regular aquarium maintenance and the use of necessary equipment. This primarily applies to filtration systems. It should also be noted that the Platinum Hatchetfish can indeed jump out of the water when threatened, but this fact has nothing to do with the idea of "flight"; many fish avoid such maneuvers.

Diet

In home aquariums, these fish become omnivorous, although in nature their diet consists mainly of small insects and other invertebrates. An important requirement for food is its buoyancy, as hatchetfish can only feed from the water surface.

Breeding and Reproduction

To date, there are no documented cases of successful breeding of hatchetfish in amateur aquariums. In nature, the spawning of these fish coincides with seasonal changes, such as periods of rain and drought, as well as migration to flooded forest areas. It is there, in quiet, food-rich backwaters, that the fry appear. Recreating such conditions in a home environment presents significant difficulties for a beginner aquarist.

Diseases

Maintaining a stable biological system, providing a balanced diet, and eliminating stress factors (e.g., harassment by aggressive tank mates) are the best guarantees for preserving fish health. If the first signs of illness appear, the first thing to pay attention to is precisely these three aspects, as deviations have likely occurred in one of them. As a rule, eliminating the problem leads to self-recovery. However, if the immune system proves to be insufficiently strong, medicinal treatment may be required.

How to choose

When choosing a Platinum Hatchetfish, it is important to ensure there are no external injuries, as the fish are prone to trauma during transport and jumping. Healthy individuals should actively swim in the upper water layers, have clean fins without signs of rot or white film, and display natural schooling activity. Avoid purchasing fish with sunken bellies or signs of emaciation, as this species can be sensitive to store conditions and stress from relocation. It is recommended to acquire a group of 6 or more individuals, as solitary keeping leads to significant stress and timidity.

Compatibility

There are no pair reviews for this species yet — check tankmates in the matcher.

All tankmates

Plants and this fish

Matching water does not mean the plant will stay intact.

Frequently asked questions

The essentials: size, tank volume, water parameters and care

How big does Platinum Hatchetfish get?

An adult reaches 6–7 cm in length. Plan the tank around the maximum size: the fish quickly outgrows a cramped setup.

What size aquarium does Platinum Hatchetfish need?

The recommended volume is 250 L. A smaller tank speeds up nitrate build-up and raises stress levels.

What water parameters does Platinum Hatchetfish need?

Temperature 20–28 °C, pH 5–7.5, hardness 1–15 dGH. Stability matters more than exact values: sudden swings are harder on the fish than a small deviation from the ideal.

How long does Platinum Hatchetfish live?

Around 5 years when kept properly. Lifespan depends directly on tank volume, water quality and a varied diet.

Is Platinum Hatchetfish aggressive?

Temperament: peaceful (regular). Keep this in mind when choosing tank mates.

How many Platinum Hatchetfish should be kept together?

Recommended setup: large group (10+ individuals). Ignoring this is a common cause of stress and disease.

What does Platinum Hatchetfish eat?

Diet type: floating (any). Feed small portions that are finished within a couple of minutes — overfeeding does more harm than underfeeding.

What is the scientific name of Platinum Hatchetfish?

The scientific name of the species is Thoracocharax stellatus, family Freshwater Hatchetfish (Gasteropelecidae). It also appears in the literature as: Gasteropelecus stellatus, Gastropelecus stellatus, Salmo pectoralis.

Similar fishes

Matched by family, categories and overlapping keeping conditions

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Other scientific names and conservation status

Other scientific names
Gasteropelecus stellatus, Gastropelecus stellatus, Salmo pectoralis
Categories
Characins
Conservation status
Least concernLC