About the Congo Tetra
Species Type: Freshwater Fish
Care Level: Moderate. May tolerate only a narrow range of water parameters, have specific dietary requirements including frozen or even live foods, may have behaviors that severely limit potential tankmates or may require a specialized aquarium setup.
Origin: Africa. Inhabits calm waters of streams and rivers in the Congo [Zaire] River basin. Available fish will likely be commercially raised.
Compatibility/Temperament: Very peaceful. Must be kept in a group of at least 5 but preferably more; can easily become frightened otherwise. The male is the more colourful and a mix of equal male/female is perhaps best, though less of an issue than with many other characins. In spite of its larger size and being an active swimmer, this is a timid fish and should not be combined with boisterous tankmates. Not suitable with any fish likely to nip fins.
This is the most widely-available of the many African characins and is truly a beautiful fish for the larger community aquarium. Often appearing drab and colourless in the store tank, when placed in a well-planted aquarium with a dark substrate and subdued lighting they shimmer with metallic hues of blue, green, orange and gold as they swim. Floating plants are necessary to both reduce the lighting and to calm the fish. Filter current should be minimal.
There should be an open space along the length of the tank as this fish is a very active swimmer, remaining in the upper half of the aquarium. The male is readily identified by the extended middle filaments of the caudal (tail), and is the more colourful and possesses considerably longer dorsal and caudal fins compared to the female. The first photo above shows the male on the left and female on the right. Spawning is not easy, but in the writer's (Byron) tank they spawn often, probably due to the very soft water; a typical egg scatterer among plants. The fry grow very slowly. This fish has a lifespan of approximately five years.
Congo Tetra are easily frightened, and this can occur from sudden noises. They are sensitive to toxic compounds and cannot tolerate deteriorating water quality.
The commonly-named Yellow Congo Tetra is quite similar in appearance to the subject fish but is a distinct species, Alestopetersius caudalis.
This species was initially described as Micralestes interruptus by G.A. Boulenger in 1899. The species epithet means "interrupted" and refers to the incomplete lateral line on this fish. In 1984, Paugy moved the species into the genus Phenacogrammus, the name from the Greek for "false line" that also refers to the lateral line, that was erected by Eigenmann in 1907.
All of the African tetra species are in the Family Alestidae, originally a subfamily of Characidae until Eschmeyer (1998) raised it to the status of Family. The former spelling Alestiidae is no longer valid. The name comes from the Greek alestes, meaning a miller. There are presently 109 species in 18 genera [Fishbase].
Congo Tetra Diet
Naturally feeds on worms, crustaceans, insects and some soft plant matter. In the aquarium, will readily accept prepared foods, frozen bloodworms, brine shrimp, live worms.
In nature it can attain 4.5 inches, but in aquaria usually 3.5 inches. Females are normally slightly smaller.
Minimum Tank Suggestion
Ideal water parameters for Congo Tetra
Soft to medium hard (4-18 dGH), acidic to very slightly basic (pH 6 to 7.5 but best below 7), temperature 23-27C/73-80F.