Fish, Tanks and Ponds

Fish, Tanks and Ponds
A comprehensive guide to fish

Hyphessobrycon anisitsi

Buenos Aires tetra

Buenos Aires tetra, Hyphessobrycon anisitsiBuenos Aires tetra, Hyphessobrycon anisitsi
Photos by Andy Rapson


Hyphessobrycon: Greek, hyphesson, -on, -on = a little smaller + Greek, bryko = to bite.

General Notes:

The Buenos Aires tetra is one of the hardiest and easy to keep tetras in the hobby. Although they are generally peaceful they will nip the fins of fish like guppies, angelfish and Siamese fighters or any other slow moving fish with trailing fins and smaller fish may be regarded as food but with carefully selected tank mates they will be fine. They aren't suitable for a planted aquarium either because they will nibble away at live plants. With good care you can expect Buenos Aires tetras to live for up to five years. Despite a few drawbacks this is one of the very best fish for a beginner to keep and an ideal first egg layer for the novice fish breeder.


In the wild these fish feed on worms, crustaceans, insects and plants, in captivity they are bold feeders and very easily pleased. Use a good quality flake or granular food and supplement this with live or frozen foods such as blood worms, daphnia, glass worms ect. Fresh greens such as aquatic plant cuttings, thinly sliced cucumber, blanched spinach or nori will help to keep the diet varied and the fish very healthy.


Females are larger and more rounded than the vibrantly coloured males when adult.


This is one of the very easiest characins to breed, for best results use slightly acidic water with a temp of 75°F in the usual tetra breeding set up:

Use a separate aquarium filled with soft acidic aged water and containing a small air powered sponge filter and something to act as a spawning mop such as a bunch of fine leaved plants tied in to a bunch for example. Keep the tank away from direct light and in very dim conditions because both eggs and fry of this species are light sensitive. Introduce a well conditioned pair in the evening and they will probably spawn at dawn. After spawning remove the parents to prevent them from eating all their eggs. The eggs hatch after about 24 hours but it will be another three or four days before the fry become free swimming. Add a commercially available liquid fry food to the tank about a day or so before the fry become free swimming as this will encourage the growth of infusoria which the fry can eat but don't add to much and pollute the water. Carry on using the liquid food or similar until the fry are large enough to take micro worms or newly hatched brine shrimps. They can be bred as a pair or in a group. If you breed them in a group be aware that you will have a very large number of fry which will require a great deal of space to raise and dealers won't thank you if you flood the local market with these fish and they end up stuck with them.

Wild status

The wild populations Buenos Aires tetras has not been evaluated but almost all Buenos Aires tetras offered for sale will be commercially bred ones.

Information at a glance

pH: 5.8 - 8
dGH: 4 - 25
Temperature: 18 - 28°C (64 - 82°F)
Diet: Omnivore
Size: 6cm 2.5in)
Min tank size: 100 litres
Difficulty level: Easy
Aquarium type: Community
Swimming level: Middle

Distribution and habitat

distribution map for Buenos Aires tetra, Hyphessobrycon anisitsi

Origin: South America: Paraná and Uruguay River basins.

Habitat: Due to their undemanding nature  Buenos Aires tetra are found in a multitude of habitats including: ponds, ditches, streams and rivers.


Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Characiformes
Family: Characidae
Genus: Hyphessobrycon
Species: H. anisitsi (Eigenmann, 1907)

Common name:
Buenos Aires tetra

Synonyms: Hemigrammus anisitsi, Hemigrammus caudovittatus, Hyphessobrycon erythrurus