Max Size: 7cm

Spotfin Hatchetfish (Thoracocharax stellatus)

Spotfin Hatchetfish are a well-known aquarium fish that has been popular in the hobby for decades. These fish are very peaceful, very active and not at all skittish. This Hatchetfish is well suited to a community aquarium and are ideal for a beginner aquarist as they are relatively hardy.

Spotfin Hatchetfish are a schooling species in nature, so you should therefore maintain them in groups of at least six individuals, preferably more; otherwise, without the security of their own kind, they will not settle, and you will not be able to witness their interesting natural behaviours.

Ideal tankmates for Spotfin Hatchetfish could include other species that inhabit different regions of the aquarium, such as Dwarf Barbs, Tetras, Apistogrammas, Corydoras Catfish and smaller Plecos. These fish will also coexist peacefully with other South American fish, including the Marbled Hatchetfish. However, it would be best to avoid housing these Hatchetfish with fast-moving, large, or aggressive species as they will be outcompeted for food and may become easily spooked.

The decor is unnecessary for the Spotfin Hatchetfish; however, they will appreciate an Amazon biotope-style aquarium that includes driftwood, sandy substrate and leaf litter. These Hatchetfish occasionally enjoy a current to swim against, although you should also provide some quiet places. You should also ensure that you have floating plants on the water's surface or a tight-fitting lid on the aquarium, as these fish tend to jump very high out of water for feeding.

Spotfin Hatchetfish are considered one of the largest of this species. These fish have a deep, flat body with a small mouth opening upwards. In addition, these fish are streamlined and have a bulging belly that forms a semi-circle starting at the mouth ending at the caudal peduncle. Their bodies are silver, and they have elongated pectoral fins and transparent fins except for their dorsal fin, which possesses a prominent dark spot. In addition, these fish also have fleshy raised bumps that run along their abdomen and their caudal peduncle.

Tank Mates for the Spotfin Hatchetfish

1 ideal tank mate ideas for the Spotfin Hatchetfish include:

Skunk Corydoras(Corydoras granti)
Quick Facts
Scientific NameThoracocharax stellatus
Year Described1858
Other NamesSilver Hatchetfish, Spotfin Silver Hatchetfish, Spotted Hatchetfish, Platinum Hatchetfish
OriginsArgentina, Bolivia, Brazil, Colombia, Ecuador, Paraguay, Peru, Venezuela
Aquarium LevelTop
DifficultyBeginner - Intermediate
Best kept asGroups 5+
Lifespan2 - 3 years
Water Parameters
Water TypeFreshwater
PH5.0 - 7.5
GH3 - 15
TDS18 - 215
68 - 82℉
20 - 27.8℃

Photos of the Spotfin Hatchetfish

Spotfin Hatchetfish

Natural Habitat

Spotfin Hatchetfish are widespread throughout South America and can be found in Venezuela, Brazil, Peru, Colombia, Ecuador, Bolivia, Paraguay, and Argentina. You will find them in the Amazon, Orinoco, Paraguay, Parana and Tocantins-Araguaia Basins. These fish inhabit slow-flowing to still blackwater and clear water marshes, lakes, streams, oxbows, backwaters, and floodplains, usually in areas with an abundance of riparian vegetation.

What to feed the Spotfin Hatchetfish

In the wild Spotfin Hatchetfish are primarily insectivorous that leap out of the water to take insects such as beetles, ants and mayflies from riparian vegetation. In the aquarium, these fish will reluctantly take dried foods initially; however, they will usually learn to accept them over time.

It would be best to provide these fish with a good quality dried food such as flakes as the staple diet; however, a large proportion of the Spotfin Hatchetfish's diet should consist of live and frozen foods, like daphnia, fruit flies, brine shrimp and bloodworm if available. These fish will feed on the surface but will also swim down to snap up sinking foods.

How to sex the Spotfin Hatchetfish

It is quite challenging to differentiate between male and female Spotfin Hatchetfish as they look almost identical; however, the female is usually more rounded in the abdomen, especially when she is full of eggs.

How to breed the Spotfin Hatchetfish

Breeding Spotfin Hatchetfish can be tricky in the aquarium, but they can be encouraged to spawn under the right conditions.

These Hatchetfish require a separate breeding tank with a thin layer of gravel as a substrate. The water should be mature, soft, and slightly acidic, and the temperature will need to be raised somewhat. These fish inhabit blackwaters in the wild, so adding peat into the breeding tank will help to darken and soften the water. The tank will need to be dimly lit, and you will need to supply floating plants. The plants will help reduce the light further and be used as a spawning medium. In addition, a small, air-powered sponge filter will produce filtration and mild water circulation.

The Spotfin Hatchetfish will go through a lengthy courting, after which the female will scatter eggs that will drop to the bottom of the tank. You can breed these Hatchetfish in pairs, but the best way to spawn these fish is in a small group of 4 to 6 individuals. It would help if you conditioned the breeders with a rich diet that includes plenty of small insects, crustaceans and bloodworms, as these will encourage them to spawn.

Once spawning s complete, it is advisable to remove the parents as they will consume both the eggs and fry if given a chance. The eggs will hatch approximately 36 to 48 hours later, and the fry will become free swimming one to two days after that.

The fry will require tiny foods such as infusoria, paramecium or powdered fry food for the first week or so until the fry are big enough to accept baby brine shrimp or microworm. Around 20 days after they hatch, the fry will start to develop the body shape of the adults and swim in all areas of the aquarium.

Other Hatchetfish of interest

Common Hatchetfish(Gasteropelecus sternicla)
Marbled Hatchetfish(Carnegiella strigata)
Date Added: 18/03/2022 12:56:15 - Updated: 18/03/2022 13:33:54