NEWS112
22
days to weeks) to 18 °C. In the case of
species of southern provenance (Uruguay,
Paraguay) thetemperaturecanperiodically
dropas lowas14 °C.
Appropriate feeding
The characins normallymaintained in the
aquarium can be characterized as
omnivores with a preference for carnivore
foods. They can be fed entirely without
problemon all theusual types of food for
ornamental fishes available in the trade
(i.e.dry, frozen, and live foods).Only a few
larger species feed predominantly on
vegetable food. If the fishes are observed
to consume aquatic plants then
additional vegetable food (special flake
foods,scalded lettuceordandelion leaves,
etc) shouldbeprovided.
Correctmaintenance
Characins are sensitive to a high germ
count in the water and to high levels of
nitrogenous compounds. For this reason
regular largepartialwater changes are the
most important element of maintenance.
Ideally 1/3 - 2/3 of the water should be
changed every week, refilling with
conditioned, fresh water of the same
chemistry; at the same time thedifference
in temperature between the new water
and theaquariumwater shouldbeassmall
as possible andnevermore than 2-3 °C. In
aquaria with a low fish density, minimal
germ population, and good biological
filtration,water changes canbe reduced to
1/5 of the total volume every 14 days.
Longer intervals should not be employed
in the long term.
In linewith thenatural habitat, these fishes
should always have access to secondary
plantmaterial.Dead leaves (ofSeaAlmond,
Beech,Oak,orWalnut),Alder cones,orpeat
can be utilized, or special liquid
preparationsaddedateverywater change.
Aquariumand tankmates
Characins are active fishes that need a
certain amount of swimming space for
their well-being. Tank length should be
around 10-15 times the length of the
species inquestion,with awidth tomatch
(i.e. 5-7.5 times fish length), to permit the
fishes enough room to exhibit their
species-typical swimmingbehavior.
Many species (e.g. Neons and Cardinals
(
Paracheirodon
) livenear thebottom,while
others (e.g. the majority of
Hemigrammus
and
Hyphessobrycon
species) favor the
middle layers of thewater, and yet others
(e.g. hatchetfishes (
Carnegiella, Gasterope-
lecus
and
Thoracocharax
) and tetras of the
family Lebiasinidae (
Pyrrhulina, Copeina,
Copella
)) livenear thewater'ssurface.There
are also bottom-dwelling characins with a
reduced swim bladder (
Characidium
and
others inSouthAmericaplus
Nannocharax
and relatedgenera inAfrica).
An aquarium for characins shouldprovide
plentyof cover and at the same timeoffer
open swimming space. Floatingplantswill
providean increased senseof securityand
hence well-being. A dark substrate will
encourage intensifiedcoloration.
Characins are usually peaceful among
themselvesand towardsother species.The
occasional individualmay exhibit aberrant
behavior,and replacements for losses from
anygroups present shouldbeobtained as
quicklyaspossible.
Distichodus sexfasciatus
, family Distichodidae.
Thisspeciesgrowsvery large (25 -40cm).
Poecilocharax weitzmani
, family Crenuchidae,
size:3-4cm.
Lifeexpectancy
Inthewildthemajorityofthesmallcharacins
rarely enjoy a second year of life, but in
captivity they can be astonishingly long-
lived.Small speciesusually start to show the
first signs of age at about three years old,
medium-sizedat5-8years,and largespecies
caneven live fordecades.
Size
Small characinswithaneventual sizeof less
than 5 cm are sexually mature at 12-15
weeks old, and at this point will be half to
three quarters (depending on environ-
mental conditions) of their eventual size.
Largerspecies(upto10cm)growsomewhat
more slowly and are often not full-grown
untiltheageof12months.Speciesthatgrow
larger than 10 cm usually don't reach
breedingsizeuntil their secondor thirdyear
of life.Becauseof the largevarietyofspecies,
pleasecheckthe labelonthesalesaquarium
for the potential maximum size of any
species that interestsyou.
Specialdetails
Because of their bright coloration and lively
behavior,barbs, rasboras,anddaniosare ideal
fishes for community aquaria. They do not
practiceanybroodcareandhencedonothold
territory- inotherwordstheyarepeaceful.
Nannostomus marginatus
, family Lebiasinidae,
size3 -3,5cm.
Hyphessobrycon eques
, cultivated form
”Minor”, familyCharacidae, size3 - 4 cm.
