Hemigrammus cupreus

Shiny Copper Tetra

Classification

Characidae

Distribution

Known only from the Rio Solimões, Brazil.

Habitat

The Rio Solimões is actually the section of the main Amazon river that flows from the Peruvian border until it meets the Rio Negro near the Brazilian city of Manaus. Here, the two converge in the famous ‘meeting of the waters’ phenomenon. The water in the river is full of organic sediment and dissolved chemical ions. As a result, it appears very cloudy and turbid, and is a creamy-brown colour. This type of water is commonly referred to as ‘white’ water. The river flows through a large floodplain which floods annually, raising water levels by over 10 meters. H. cupreus can therefore be found both in the river itself and in various flooded habitats, including lakes known locally as ‘várzeas’. Many of these contain rafts of floating plants commonly referred to as ‘meadows’.

Maximum Standard Length

1.4″ (3.5cm).

Aquarium SizeTop ↑

A shoal would need a tank of around 24″ x 15″ x 12″ (60cm x 37.5cm x 30cm) – 70 litres.

Maintenance

A biotope setup would be very simple to arrange. Use a substrate of river sand and add a few driftwood branches (if you can’t find driftwood of the desired shape, common beech is safe to use if thoroughly dried and stripped of bark) and twisted roots. This is all that is required. Submerged aquatic plants are not a feature of this species‘ natural waters. Floating plants do occur and can be used if you wish. Use fairly dim lighting.

Alternatively, it also does well in a well maintained, heavily planted tank. As any of these seen for sale will almost certainly be wild caught a more general setup is not really suitable.

Water Conditions

Temperature: 74-80°F (23-27°C)

pH: Conditions in the white water Rio Solimões are far less acidic than in black water habitats. Somewhere in the range 6.5-7.2 would be an accurate representation.

Hardness: 5-15°H

Diet

Omnivorous and will accept just about anything offered. Feed a mixture of dried flakes and granules along with small live and frozen foods.

Behaviour and CompatibilityTop ↑

It’s a very peaceful species that won’t compete well with very boisterous or much larger tankmates. Ideally, keep it with other South American species, such as other Hemigrammus or Hyphessobrycon species, pencil fish, Apistogramma dwarf cichlids, Corydoras and small Loricariids. In a more general community, it can be combined with smaller rasboras, barbs, Anabantoids and West African dwarf cichlids such as Pelvicachromis species.

Always buy a group of at least 6 of these, preferably 10 or more. It is a shoaling species by nature, and will fare much better when in the company of its own kind. Like most tetras it actually looks far more effective when maintained like this anyway.

Sexual Dimorphism

Adult males tend to be smaller, slightly more colourful and slimmer than females.

Reproduction

Unreported, but it can most likely be bred in a similar way to other species in the genus. You’ll need to set up a separate tank if you want to raise decent numbers of fry. Something around 18″ x 10″ x 10″ in size is fine. This should be very dimly lit and contain clumps of fine-leaved plants such as java moss or spawning mops, to give the fish somewhere to deposit their eggs. Alternatively, you could cover the base of the tank with some kind of mesh. This should be of a large enough grade so that the eggs can fall through it, but small enough so that the adults cannot reach them. The water should be slightly soft and acidic in the range pH 6.5-7.0, gH 1-10, with a temperature of around 80-84°F. Filtering the water through peat is useful, as is the use of RO water. A small air-powered sponge filter bubbling away very gently is all that is needed in terms of filtration.

Most Hemigrammus can be spawned in a group, with half a dozen specimens of each sex being a good number. Condition these with plenty of small live foods and spawning should not present too many problems.

Alternatively, try spawning it in pairs. Under this technique the fish are conditioned in male and female groups in separate tanks. When the females are noticeably full of eggs and the males are displaying their best colours, select the fattest female and best-coloured male and transfer them to the spawning tank in the evening. They should spawn the following morning.

In either situation, the adults will eat the eggs given the chance and should be removed as soon as eggs are noticed. These will hatch in 24-36 hours, with the fry becoming free swimming a 3-4 days later. They should be fed on an infusoria–type food for the first few days, until they are large enough to accept microworm or brine shrimp nauplii. The eggs and fry are light sensitive in the early stages of life and the tank should be kept in darkness if possible.

NotesTop ↑

Not a common species in the hobby, although it does occasionally show up as a contaminant among imports of more popular species.

Like all Hemigrammus, the taxonomic status of this species is currently Incertae Sedis, meaning uncertain. The genus is currently used as something of a catch-all for over 70 species of small characin. Most experts agree that a full revision is required, with the likely outcome that many species will be placed into new or different genera.