Product Details

Royal Black Arrow Tetra – Inpaichthys luizae

The Royal Black Arrow Tetra is a newly described and highly attractive South American tetra with a sleek body, bold dark arrow-like stripe and vivid display colours in mature fish. Also known as the Black Arrow Tetra or Black Arrow Royal Tetra, this rare species is best suited to mature planted aquariums with calm tank mates, stable water quality and a proper group. It is a superb choice for aquarists looking for an unusual small tetra with strong visual impact and active social behaviour.

Key Identification:

Common Name: Royal Black Arrow Tetra
Other Names: Black Arrow Tetra, Black Arrow Royal Tetra
Scientific Name: Inpaichthys luizae
Fish Type: Tetra / Small Characin
Water Type: Freshwater

Natural Range & Habitat:

Inpaichthys luizae is native to Brazil, where it is known from tributaries of the rio dos Peixes in Mato Grosso State. The rio dos Peixes is part of the rio Juruena drainage, within the wider rio Tapajós basin.

Its natural habitats are described as well-preserved tributary waters, likely with clean water, aquatic cover and quieter marginal areas suitable for small shoaling tetras. In the aquarium, this species should be treated as a small tropical South American tetra that benefits from mature planted conditions, gentle flow, shaded areas and stable water quality.

Appearance & Adult Size:

Royal Black Arrow Tetras have a slender, elegant body with a distinctive dark oblique stripe running from the lower side of the body towards the caudal fin, creating the “black arrow” appearance. Mature fish may show attractive metallic, blue, violet, red or warm reflective tones depending on sex, mood, lighting and condition.

Adults are small, usually reaching around 3–4 cm. Females may become slightly larger and fuller-bodied than males, while mature males often show stronger display colour and more active sparring behaviour.

Aquarium Suitability:

This species is best suited to mature planted aquariums, peaceful South American-style displays and specialist tetra communities. It should be given open midwater swimming space along with plants, driftwood, leaf litter or shaded areas for security.

Royal Black Arrow Tetras are not suitable for aggressive communities, large predatory fish or unstable new aquariums. Because this is a rare and recently described fish, it is best kept by aquarists who can maintain stable conditions and, where possible, prioritise captive breeding.

Recommended Aquarium Size:

A practical minimum is 60 litres for a group, with 80 litres or more preferred for a larger shoal and mixed peaceful community.

Keep in a group of at least 8, with 10 or more preferred where space allows. A proper group helps reduce stress, spreads male display behaviour and encourages the best colour.

Water Conditions:

Temperature: 23–27°C
pH: 6.0–7.2
Hardness: Soft to moderately hard
Additional Notes: Stable, clean water is important. Gentle to moderate filtration, planted cover and regular water changes are recommended. Avoid immature aquariums, sudden parameter swings, poor water quality and very hard alkaline extremes.

Temperament & Tank Mates:

Aquarium Category: Community Fish

Royal Black Arrow Tetras are generally peaceful shoaling fish, although males may flare, chase and display to each other. This behaviour is usually harmless in a good-sized group with enough space and cover.

Suitable tank mates include small tetras, pencilfish, peaceful rasboras, dwarf cory-type catfish, Otocinclus, small peaceful gourami and calm dwarf cichlids in suitable water. Avoid large predators, aggressive cichlids, fin-nipping species, very boisterous barbs and fast-feeding fish that may intimidate them.

Feeding:

Royal Black Arrow Tetras are small omnivorous micropredators. In nature, similar small characins feed on tiny aquatic invertebrates, insect larvae, crustaceans and zooplankton. In the aquarium, offer fine flakes, micro pellets and small slow-sinking granules as the staple diet.

Supplement regularly with small frozen or live foods such as daphnia, cyclops, baby brineshrimp, mosquito larvae and finely chopped bloodworm. A varied diet helps maintain colour, body condition and display behaviour.

Behaviour in the Aquarium:

This is an active midwater tetra that looks best in a group. Settled fish will move through open swimming areas and planted cover, with males often displaying to one another by intensifying colour, flaring fins and holding small positions within the shoal.

They are likely to show better confidence in a calm aquarium with dark substrate, plants and gentle lighting. Breeding may be possible in soft, clean water with fine-leaved plants or spawning mops, although adults may eat eggs and fry.

Care Notes:

Keep this species in a proper group and add only to a mature, stable aquarium. Provide planted cover, clean water, gentle flow and small foods.

Because Inpaichthys luizae is rare and recently described, avoid mixing it with similar Inpaichthys species if breeding or maintaining a pure group is important. Regular water changes, low stress and careful acclimation are recommended, especially for newly imported fish.

Recommended For:

Intermediate

Availability:

Rare / Specialist import, with captive-bred availability likely to remain limited

Image Disclaimer:

All images are a visual representation of the fish you will receive, made to be as accurate as possible. Natural variation in size, colour, pattern, body tone and markings can occur between individual fish.