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Maximum size : 5 cm

Black Ruby Barb - Pethia nigrofasciata : Complete Fish Profile & Care Guide

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The Ruby Barb (Pethia nigrofasciata) is a stunningly vibrant, peaceful, and small fish that makes a perfect addition to a diverse community aquarium. Hardy and adaptable, they display their best colors and confidence when provided with the right tank conditions. The Black Ruby Barb thrives in its natural shoaling behavior, making it essential to keep them in groups of 6 or more. To create a comfortable environment, furnish the aquarium with dark decor and an abundance of plants, including floating ones that provide much-appreciated shady hiding spots. However, be mindful that they tend to nibble on fine-leaved plants, so choose your aquatic flora carefully. Black Ruby Barbs are sensitive to poor water quality and rapid changes in water chemistry, making it prudent to conduct regular partial water changes instead of infrequent, large-scale adjustments. By attending to these details, you'll create a thriving and harmonious environment for these enchanting fish. This captivating species of barb features a pointed, deep purple-red head, a high back, and a ruby-red body. They are adorned with three striking black bands that run vertically through their body, adding to their alluring appearance. Black Ruby Barbs are classified as vulnerable in their natural habitat. To protect the remaining wild populations, all specimens available in the trade today are captive-bred. This practice helps to conserve and safeguard the species in their native environment.

Black Ruby Barb Photos

Sexual Dimorphism

Distinguishing between male and female Black Ruby Barbs is relatively straightforward due to several notable differences. Males exhibit a more intense ruby hue, which is visible not only on their bodies but also on their dorsal and anal fins. In contrast, females display a paler coloration, with only the base of their dorsal fin turning black. Additionally, females possess more rounded bellies and tend to grow slightly longer than their male counterparts.

Quick Facts

Scientific NamePethia nigrofasciata
Year Described1868
Other NamesPurple-Headed Barb, purple head barb, ruby barb, black barb
OriginsSri Lanka
Max Size5 cm
Aquarium LevelBottom - Middle
Best kept asGroups 5+
Lifespan3 -4 years

Water Parameters

Water TypeFreshwater
PH5.5 - 7.5
GH5 - 12
TDS36 - 268
72 - 79
22.2 - 26.1

Natural habitat

Black Ruby Barbs are fascinating fish that hails from the serene, clear mountain streams found in the Niwala and Kelani river basins of Sri Lanka, South Asia. These majestic creatures prefer to reside in soft acidic waters that are cooler, shaded, and slow-flowing, making them a truly unique and exotic species. In their natural habitat, Black Ruby Barbs can be found in areas with dense vegetation, where they can thrive among the fine sand or gravel substrate. Their ideal environment is one that is covered by a layer of leaf litter, fallen branches, and twigs, creating a complex and dynamic ecosystem that supports their growth and development. Overall, Black Ruby Barbs are a magnificent species that offer an intriguing glimpse into the diverse and beautiful world of aquatic life.

How to breed the Black Ruby Barb

Breeding Black Ruby Barbs is relatively simple, provided you adhere to the appropriate conditions. These fish can be bred in groups or pairs. Ensure that the breeding tank has soft, acidic water and is filled with fine-leaved plants such as Java moss. If unavailable, spawning mops can serve as an alternative. Keep the lighting dim, as the eggs are sensitive to bright light. Feeding the barbs live or frozen foods like bloodworms or brine shrimp will encourage spawning and promote the production of high-quality, healthy eggs, resulting in robust fry. You can identify the onset of spawning by observing the male courting the female, swimming around her while displaying his fins. This process may take several hours, and the pair can produce up to 100 eggs, which they will scatter among the plants. As with many other fish species, it is crucial to remove the adult fish once the eggs have been laid to prevent them from consuming the eggs. The eggs typically hatch within 24 hours, and the fry become free-swimming approximately 24 hours after hatching.

Diet & feeding

Black Ruby Barbs have simple dietary needs, but for optimal coloration and overall health, provide them with regular servings of small live and frozen foods such as Daphnia, Artemia, and bloodworms. As the primary component of their diet, offer them high-quality dried granules and flakes, ideally containing some algae or plant content.

Frequently asked questions

Black Ruby Barbs can grow up to a maximum length of 8 centimetres, with the female usually being slightly longer than males.

Black Ruby Barbs generally have a peaceful disposition and can be somewhat shy. Therefore, these fish are best kept in groups of 6 or more individuals. However, these Barbs misbehave in small groups as the stress from being isolated virtually always comes out as aggression towards other tankmates.

In the aquarium, Black Ruby Barbs are unfussy and easily fed. However, suppose you would like the best condition and colours of your fish. In that case, you should offer regular meals of small live and frozen foods such as artemia, bloodworm and daphnia, alongside high quality dried food such as flakes and granules, some of which must include additional plant and algal content.

When it comes to Black Ruby Barbs, the choice of decor is not particularly critical; however, these fish seem to display better colouration in a heavily planted aquarium with a dark substrate. Adding some driftwood roots or branches, floating plants, and leaf litter also appears to be appreciated and adds a more natural feel. Strong filtration is not required; however, they seem to enjoy a certain level of water movement and will thrive in a hill stream-type aquarium set-up.

Black Ruby Barbs are endemic to the Nilwala and Kelani river basin alongside other more minor drainages between them in the southwestern islands of Sri Lanka in South Asia. Their natural habitat consists of several small, pristine streams containing clear or slightly stained, shallow water. Not much sun can penetrate the forests floor, so these aquatic habitats are shaded, and the water temperature is usually relatively cool.

Black Ruby Barbs have no unique demands in terms of water chemistry; therefore, you can combine them with a majority of popular fish in the aquarium hobby, such as other small Cyprinids as well as Livebearers, Rainbowfish, Tetras, Loaches, Anabantoids and Catfish.

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