Cyprinids (Cyprinidae)

Arulius Barb

Dawkinsia arulius

The Arulius Barb, scientifically known as Dawkinsia arulius and belonging to the family Cyprinidae, does not impress with its bright coloration or unique body pattern. However, its lively activity and unpretentiousness attract attention, making observing it quite interesting. Thanks to its hardiness and ease of keeping and breeding, this fish is well-suited even for beginner aquarists.

Tank
from 243 L (64 gal), 250 L (66 gal) recommended
Temperature
19 – 25 °C (66 – 77 °F)
Size in aquarium
10 – 12 cm (3.9 – 4.7 in)
Acidity
pH 6–7.5
Natural rangeRange on the map
  • Southern India area
  • Western Ghats area
  • India

Tank conditions

Plan the tank stocking
Temperature
19 – 25 °C (66 – 77 °F)
Water pH
Slightly acidic (6) – Neutral (7.5)
Water dH
Very soft (2) – Medium hardness (10)
Water salinity
no salt (freshwater)
Size in aquarium
10 – 12 cm (3.9 – 4.7 in)
Lifespan
7 years
Temperament
Peaceful, active/mobile
Toward small fish
not a predator
Required aquarium volume
from 243 L (64 gal), 250 L (66 gal) recommended
Lighting
moderate (regular)
Substrate
rocky rock formations, boulders, etc.
Water flow
moderate or strong
Swimming level
middle level
Feeding
Any (universal)
Keeping
Group (8–10 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. The 243 L minimum corresponds to a tank footprint of 120×45 см. The recommended 250 L is for the group size given under keeping mode.

Care and keeping

Description

On its large, yet robust, light-toned body, there are wide vertical dark stripes that run from the back and slightly fade towards the belly. The fins, especially the caudal fin, have a reddish tint. Males stand out with more intense coloration compared to females, although they are smaller in size. As they reach sexual maturity, white spots or tubercles can be observed in the mouth area of males.

Habitat

The species originates from South India, where the Arulius Barb inhabits clear, flowing, oxygen-rich waters. These are typically small streams and rivers with rocky bottoms composed of gravel, pebbles, and boulders. During the summer, this area is subject to monsoons, leading to significant changes in water levels. Unfortunately, human economic activity has caused significant damage to the species' natural habitat, contributing to a decline in wild populations, and in some areas, they have completely disappeared.

Behavior and Compatibility

This peaceful, active schooling species requires keeping in a group of at least 8 individuals. Arulius Barbs get along well with almost all fish of similar size and temperament. However, it is recommended to avoid cohabitation with very large and aggressive species, as well as with small and/or slow-moving fish.

Care and Maintenance

For a school of 8–10 individuals, an aquarium of about 250 liters will be required. When decorating it, preference should be given to robust plants with well-developed root systems, capable of withstanding strong water currents; floating plants are not recommended. Due to the characteristics of the current, a sand substrate is not used; instead, it is better to use stones, boulders, or gravel. The choice of other decorative elements is at the discretion of the aquarist. Optimal water parameters for these fish are slightly acidic values, close to neutral, with low hardness. More detailed information on pH and dGH values, as well as methods for their correction, can be found in the "Hydrochemical composition of water" section. Barbs are very sensitive to the accumulation of organic waste and oxygen deficiency, so the main attention when setting up an aquarium should be given to the filtration system. Choose the most powerful filter that suits your capabilities. In addition to water purification, it helps create the necessary internal current, making conditions for the Arulius Barb as comfortable as possible. Although many filtration systems aerate the water, installing additional oxygen diffusers will not be superfluous. Other equipment includes a heater and lighting fixtures, which are most often supplied with the aquarium lid. Regular care includes weekly water changes of 30–50% of the total volume with fresh water, as well as periodic cleaning of the substrate from organic deposits and, if necessary, removing plaque from the glass with a scraper.

Diet

To maintain the health of the Arulius Barb, a balanced diet consisting of approximately equal parts of live and dry foods is recommended. The fish readily accept bloodworms, daphnia, as well as various flakes and granules. When using exclusively dry foods, it is important to ensure that their composition is enriched with protein. A lack of protein components can cause health problems due to a deficiency of essential micronutrients. Feeding is done 2–3 times a day, in portions that the fish can consume within 5 minutes. It is important to promptly remove any uneaten food remnants from the aquarium.

Breeding and Reproduction

Fish do not have well-developed parental instincts; after spawning, they are prone to eating their own eggs. Therefore, a separate tank should be used for successful breeding. A spawning aquarium of about 15–20 liters should be equipped with a rocky substrate over which a fine-mesh net will be stretched. Through this net, the eggs can fall, becoming inaccessible to the parents. As additional protection for the offspring, dense thickets of small-leaved, low-growing plants and mosses can also be used. The aquarium is filled with "mature" water from the main tank. For equipment, a simple sponge filter, heater, and aerator are sufficient; creating a strong internal current is not recommended in this case. Lighting is not critical, as spawning often occurs in dim light. The breeding period can begin at any time, so it is advisable to always keep the spawning tank ready. When several females are visibly rounded, they, along with selected males, are transferred to the prepared spawning tank. After the process is complete, the parents are returned. Fry hatch after 1–2 days and begin free swimming after another 24 hours. In their first days of life, they need to be fed microscopic foods, such as Artemia nauplii or microworms.

Diseases

The most common cause of diseases is suboptimal keeping conditions. In turn, a stable and balanced biological system in the aquarium significantly reduces the risk of their manifestation.

How to choose

When choosing an Arulius barb, it is important to pay attention to the general health and activity of the individuals. A healthy fish should be active, show interest in its surroundings, and not have signs of emaciation. Carefully examine the skin: there should be no ulcers, white spots, fin damage, or signs of parasitic infections on the body. Avoid purchasing fish that appear sluggish, stay at the water surface, or, conversely, constantly hide in the corners of the aquarium. Consider the following features when purchasing: — acquire a group of 6–10 individuals, as solitary keeping causes severe stress for this species; — remember that pale coloration in the store is often a sign of stress, not disease, however, the color should intensify when conditions normalize; — sexually mature males in spawning condition may have small white tubercles around the mouth area, which is normal and not a sign of infection.

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 Arulius Barb get?

An adult reaches 10–12 cm in length. Plan the tank around the maximum size: the fish quickly outgrows a cramped setup.

What size aquarium does Arulius Barb need?

The recommended volume is 250 L. A smaller tank speeds up nitrate build-up and raises stress levels.

What water parameters does Arulius Barb need?

Temperature 19–25 °C, pH 6–7.5, hardness 2–10 dGH. Stability matters more than exact values: sudden swings are harder on the fish than a small deviation from the ideal.

How long does Arulius Barb live?

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

Is Arulius Barb aggressive?

Temperament: peaceful, active/mobile. Keep this in mind when choosing tank mates.

How many Arulius Barb should be kept together?

Recommended setup: group (8–10 individuals). Ignoring this is a common cause of stress and disease.

What does Arulius 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 Arulius Barb?

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

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Other scientific names and conservation status

Other scientific names
Barbus arulius, Puntius arulius, Systomus arulius
Categories
Cyprinids
Conservation status
EndangeredEN