Tropical Fish: Hatchets

Marble Hatchet Fish

Carnegiella strigata species

The marbled hatchetfish found in the local fish store are all caught in the wild they have been spawned, but not on a commercial basis. Also, there are at least two species, and probably some others, that come in under the common name of marbled hatchetfish.

When it comes to care, the difference of species is not important because the aquarium requirements for all of them are the same. The first and most important thing to remember about these fish is that they are world class jumpers, and unless the tank is covered tightly they will end up on the floor.

At the same time, what makes this a problem is also part of their charm in that they are one of the few fish that swim almost entirely in the uppermost regions of a tank. And, as you can easily tell from looking at their mouth, they take food exclusively from the surface, although they will take live baby brine shrimp that are just below the surface.

Hatchetfish will readily take flake food as long as it is floating on the surface of the water. They will relish any small insects you may drop on the water surface (making sure, of course, that the insects have not been exposed to any bug sprays). Their tank should have floating plants over as much of the surface as possible.

These fish will be much more comfortable if they can hang out under floating plants. Once they have become acclimated, hatchets usually do very well, which means it's best you buy only those that have been doing well in the local fish store's tanks for a week or more. And, of course, make sure you quarantine them before introducing them to your community tank.

Breeding Hatchetfish:

Hatchetfish are egg scatterers that do not tend their eggs or fry and so a separate spawning/fry tank is needed. Spawning occurs between pairs. However, in most species breeding is very difficult to achieve.

Sexes are difficult to distinguish, but females may be plumper when ready to breed. To bring the adults into breeding condition, plenty of frozen foods should be included in the diet, and the water should be kept soft, slightly acid and with blackwater extract added.

The breeding tank should be well planted and extra blackwater extract should be added so that the water is noticeably colored. The temperature should be 26°C. Fine leaved and floating plants should be used to collect the eggs. A bare bottom is recommended so that the tank can be kept very clean. After spawning the parents should be removed.

The eggs hatch after about 30 hours. Very fine live foods, e.g. infusoria, are usually needed to raise the fry. Frequent feeding is important, as are daily water changes to keep water quality high.

Hatchet fish are a little more demanding than some fish, but not overly difficult to keep. Frozen foods must be offered and the tank must be covered.

Compatibility: Discus, Angelfish, Tetras, Danios, Rasboras, Livebearers, Loaches, Plecos, and peaceful scavenger Catfish.

Hatchetfish Care:

Hatchetfish need a tank with swimming room and like a strong current. The tank must be covered as they are excellent jumpers. Most will tolerate pH around neutral and moderate hardness, but the water must be well-oxygenated.

Hatchetfish are active but peaceful schooling fish. They will not damage plants so are quite suited to planted aquariums. In community tanks, avoid mixing them with species that are too aggressive.

They are schooling fish and will not be happy unless kept in a group of at least five of their own species.