Classification:
Order: Characiformes
Family: Characidae
Distribution:
The type locality was originally given as ‘near Iquitos’, referring to the city of that name in the rainforest of Loreto region, Peru, although the specimens themselves derived from an aquarium import, and even today the true extent of its distribution remains unclear.
Habitat:
Mostly inhabits forest streams and minor tributaries rather than turbid (whitewater) main channels. The water is typically acidic, of negligible carbonate hardness and conductivity and stained brownish due to the presence of humic substances released by decomposing organic matter, although it’s also been collected from similar habitats containing transparent, unstained clearwater. The substrate tends to be covered in fallen branches, tree roots and leaf litter and in some habitats aquatic plants may also be present.
Maximum Standard Length:
20 – 30mm.
Aquarium Size:
An aquarium with base dimensions of 60 x 30cm or larger is recommended. It is advised to find a filter which has a water flow between 4-5 times the volume of your aquarium.
Maintenance:
Maintenance presents few problems although it perhaps looks best in an arrangement comprising a sandy substrate plus some driftwood roots and branches. The addition of dried leaf litter would further emphasise the natural feel and as well as offering additional cover for the fish brings with it the growth of microbe colonies as decomposition occurs. These can provide a valuable secondary food source for fry and the humic substances released by the decaying leaves are also considered beneficial, with alder cones also useful in this respect. There’s no need to use natural peat, the collection of which is both unsustainable and environmentally-destructive. This species seems to do best under fairly dim lighting but you can add aquatic plant species that can survive under such conditions such as Microsorum, Taxiphyllum or Cryptocoryne spp., while floating vegetation, such as Ceratopteris spp., is also appreciated. The vast majority of fish available in the aquarium trade are produced on a commercial basis and are more adaptable than wild specimens.
Water Conditions:
Temperature: 21 – 25°C
pH: 4.0 – 7.5
Hardness: 18 – 215ppm
Diet:
Likely to be omnivorous feeding on small invertebrates, crustacea, filamentous algae, fallen fruit and suchlike in nature. In aquaria it may survive on a diet of dried foods but like most fishes does best when offered a varied menu which in this case should also contain live and frozen chironomid larvae (bloodworm), mosquito larvae, Daphnia, Moina, etc.
Behaviour and Compatibility:
Generally peaceful making it an ideal resident of the well-researched community aquarium. It’s perhaps best-maintained alongside similarly-sized characids, gasteropelecids, lebiasinids, smaller callichthyid or loricariid catfishes and non-predatory, small-to-medium-sized cichlids. Try to buy a mixed-sex group of at least 8-10 specimens, include other schooling fishes to provide security, and you’ll be rewarded with a more natural-looking spectacle.
Sexual Dimorphism:
Sexually mature females are normally noticeably rounder-bodied and a little larger than males.
Reproduction:
You’ll need to set up a dedicated tank if you want to raise decent numbers of fry. 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 soft and acidic in the range pH 5.5-6.5, gH 1-5, with a temperature of around 28-30°C. A small air-powered sponge filter bubbling away very gently is all that is needed in terms of filtration. It 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 shouldn’t present too many problems.
The adults can be removed once eggs are noticed, or in a very heavily planted tank left in situ and fry siphoned from the tank as they’re noticed. In terms of productivity, it’s best spawned in pairs. Under this technique the fish are conditioned in male and female groups in separate tanks, or via the use of a tank divider. 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. If no eggs have appeared after a couple of days remove them and try a different pair. 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’re 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.
