Cyprinids (Cyprinidae)

Asoka Barb

Systomus asoka

The Asoka Barb, known in scientific literature as Systomus asoka, belongs to the carp family (Cyprinidae). This species is endemic and found exclusively in the river systems of Sri Lanka, located in South Asia. It prefers to inhabit sections of rivers characterized by fairly swift, and sometimes turbulent, currents. Adult fish find refuge in the headwaters, choosing relatively deep areas – up to two meters – where they stay near the bottom among rocky substrates. Notably, juveniles, or fry, behave differently: they live in the lower reaches, preferring shallow waters with calm currents, and often form large schools.

Tank
from 500 L (132 gal)
Temperature
25 – 30 °C (77 – 86 °F)
Size in aquarium
25 cm (9.8 in)
Acidity
pH 6.5–7.5
Natural rangeRange on the map
  • Sri Lanka

Tank conditions

Plan the tank stocking
Temperature
25 – 30 °C (77 – 86 °F)
Water pH
Neutral (6.5) – Neutral (7.5)
Water dH
Very soft (2) – Hard (15)
Water salinity
no salt (freshwater)
Size in aquarium
25 cm (9.8 in)
Lifespan
7 years
Temperament
Peaceful (regular)
Toward small fish
not a predator
Required aquarium volume
from 500 L (132 gal)
Lighting
moderate or bright
Substrate
rocky rock formations, boulders, etc.
Water flow
moderate or strong
Feeding
Any (universal)
Keeping
Small group 5–6 individuals
  • Lifespan. A lifespan to expect under good care, not a measured value: it depends heavily on tank volume, water quality and diet — and for selectively bred forms, on their origin as well.
  • Toward small fish. Based on the Predators category in the catalog or the temperament in the species parameters. “A risk to small fish” means the species is not a predator by habit, yet will swallow any fish that fits in its mouth.
  • Required aquarium volume. This is a husbandry recommendation, not a measured value: the volume depends on the keeping mode (small group (5–6 individuals)), footprint, decor and tank mates.

Care and keeping

Description

These fish grow up to 25 cm in length. Their body is elongated, and their head is large. The fins are short and translucent, and the coloration is silvery, complemented by a dotted pattern of horizontal stripes. A distinct black spot is noticeable at the base of the caudal fin. Sexual dimorphism in this species is weakly expressed; males and females show practically no differences in appearance.

Habitat

The species is endemic to Sri Lanka, inhabiting the upper reaches of the Kelani River and the Sitawaka River. The fish prefer areas with fast currents, clean, and well-aerated water. In nature, adults stay at depths of 1–2 meters over a rocky or sandy bottom, while juveniles inhabit shallow coastal zones.

Behavior and Compatibility

A peaceful but active fish, this barb coexists well with members of its own species and with other non-aggressive fish capable of adapting to conditions with moderate or strong currents.

Care and Maintenance

For a group of 5–6 adult Asoka Barbs, an aquarium of 500–600 liters is recommended. The aquascape should aim to recreate the atmosphere of a mountain river: large boulders and rock formations will be very suitable. A few snags, securely anchored in the substrate, can also be added. It is fundamentally important to provide internal current in the aquarium; this can be achieved with a powerful filtration system or by installing separate powerheads. For successful long-term keeping, it is necessary to constantly maintain stable water parameters and a high level of dissolved oxygen. As for diet, the fish are undemanding; they can be offered dry sinking foods (granules, tablets), enriched with all necessary vitamins and trace elements.

Diet

These fish are not demanding about their diet. Sinking dry foods, such as granules or tablets, are an optimal choice, provided they contain all the necessary vitamins and trace elements for health.

Breeding and Reproduction

Data on breeding in captivity is limited, and the species is considered difficult to reproduce. Partial water changes with distilled water are sometimes used as a spawning stimulus. The eggs are scattered chaotically throughout the aquarium, so a separator net on the bottom is recommended to protect the offspring from being eaten by the parents. After spawning is complete, the parents should be removed.

Diseases

The species is sensitive to water quality and the accumulation of nitrogenous compounds, making effective filtration a mandatory condition for keeping them. Characteristic diseases include skin and gill flukes, trichodinosis, and mycobacteriosis. Prevention is based on maintaining stable environmental parameters, regular water changes, and preventing hypoxia.

How to choose

When purchasing, choose active, mobile specimens without visible damage to fins or scales. As the species is endangered in the wild, it is important to ascertain the fish's origin—preference should be given to specimens bred in captivity. Avoid individuals showing signs of emaciation, sluggish behavior, or apathy.

Compatibility

There are no pair reviews for this species yet — check tankmates in the matcher.

All tankmates

Plants and this fish

Matching water does not mean the plant will stay intact.

Frequently asked questions

The essentials: size, tank volume, water parameters and care

How big does Asoka Barb get?

An adult reaches 25 cm in length. Plan the tank around the maximum size: the fish quickly outgrows a cramped setup.

What size aquarium does Asoka Barb need?

The recommended volume is 500 L. A smaller tank speeds up nitrate build-up and raises stress levels.

What water parameters does Asoka Barb need?

Temperature 25–30 °C, pH 6.5–7.5, hardness 2–15 dGH. Stability matters more than exact values: sudden swings are harder on the fish than a small deviation from the ideal.

How long does Asoka Barb live?

Around 7 years when kept properly. Lifespan depends directly on tank volume, water quality and a varied diet.

Is Asoka Barb aggressive?

Temperament: peaceful (regular). Keep this in mind when choosing tank mates.

How many Asoka Barb should be kept together?

Recommended setup: small group (5–6 individuals). Ignoring this is a common cause of stress and disease.

What does Asoka Barb eat?

Diet type: any (universal). Feed small portions that are finished within a couple of minutes — overfeeding does more harm than underfeeding.

What is the scientific name of Asoka Barb?

The scientific name of the species is Systomus asoka, family Cyprinids (Cyprinidae). It also appears in the literature as: Barbichthys asokae, Barbus asoka, Puntius asoka.

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Other scientific names and conservation status

Other scientific names
Barbichthys asokae, Barbus asoka, Puntius asoka
Categories
Cyprinids
Conservation status
Critically endangeredCR