Redline Rasbora

Rasbora pauciperforata

Cyprinids
Reviewed by Guidarium Editorial DeskUpdated May 11, 2026

A slender, elegant schooling fish native to the blackwater peat swamps of Southeast Asia. Distinguished by a brilliant, glowing neon-red stripe running from its mouth to its tail. They are true blackwater fish, requiring soft, acidic water and plenty of tannins from leaf litter or driftwood to thrive and show their best colors. Peaceful but can be skittish if not kept in appropriately large schools with overhead cover.

Redline Rasbora At a Glance

Adult Size7 cm
Body ShapeFusiform
Growth RateModerate
TemperamentPeaceful
Water TypeFreshwater Only
Flow PreferenceLow
Waste OutputLow
StockingSchool of 6+

Redline Rasbora Tank Requirements

Minimum Volume80 L
Minimum Length80 cm
FlowLow
Water TypeFreshwater Only
Must-Haves in the Tank
Leaf Litter/BlackwaterDriftwood (Digestion/Hiding)Plants - Densely coveredPlants - Floating
Stocking calculator

Will Redline Rasbora fit in your tank?

Care guides tell you what Redline Rasbora needs, the next question is whether your tank can safely provide it. Test Redline Rasbora against your tank size, maintenance needs, and the fish you already keep before you buy.

Redline Rasbora
Test in my tank

Redline Rasbora Water Parameters

Temperature2227°C
pH46.8
Hardness18 dGH

Redline Rasbora Temperament & Compatibility

Aggression LevelPeaceful
1/10
Where They Swim
Surface
Mid-level
Bottom
Stocking Guidelines
Keep at Least6 fish
Max per TankNo limit
Can Live Alone?No — needs a group
Behavior Traits
Hyperactive / Fast SwimmerShy / Slow Moving (Easily Stressed)Jumper (Lid Required)

Redline Rasbora Varieties

Each variety inherits the species defaults above. Only differences are highlighted.

Standard

Same care requirements as the base species

Also known as: Wild Type, Unsexed

Redline Rasbora Care Guide Summary

The Redline Rasbora, scientifically known as Rasbora pauciperforata, belongs to the Cyprinids family group. Adults reach a maximum size of approximately 7 cm and have a fusiform body shape with a moderate growth rate. Classified as peaceful, this species primarily occupies the surface and mid-level zones of the aquarium and produces a low level of biological waste.

To thrive, the Redline Rasbora requires a freshwater only aquarium with a minimum volume of 80 litres and a tank length of at least 80 cm. Water temperature should be maintained between 22°C and 27°C, with a pH range of 46.8 and a general hardness of 18 dGH. A low water flow is preferred.

Due to its specialist needs, the Redline Rasbora is best suited for fishkeepers who can provide a carefully planned setup. The Redline Rasbora is typically available in one standard form.

Redline Rasbora Habitat Setup

When setting up an aquarium for the Redline Rasbora, a low water flow best suits their natural preferences. Because this species occupies the surface and mid-level zones, the aquarium layout should prioritise adequate surface area with floating cover to make them feel secure near the waterline and open swimming space in the centre of the tank for free movement. Useful additions include driftwood, which can serve as both a hiding place and a dietary supplement, leaf litter or blackwater tannins to replicate their natural soft-water habitat, dense planting to provide cover, break sightlines, and reduce stress, and floating plants to diffuse overhead light and create shaded areas. Keepers should note that a tight-fitting lid is essential, as this species is a known jumper.

Redline Rasbora Compatibility Notes

Classified as peaceful, the Redline Rasbora is a schooling species that feels most secure in a sizeable group, where natural shoaling behaviour reduces stress and brings out their best colours. Selecting tankmates that favour different water layers from the surface and mid-level zones can help reduce competition and territorial overlap.

Who Redline Rasbora Is Actually For

Redline Rasbora is best for a fishkeeper who wants a species that can settle into a calmer community setup and can provide a keeper who can commit to a proper group of at least 6. It makes the most sense for a hobbyist who will actually build around its needs, especially leaf litter/blackwater.

The most common mistake is buying Redline Rasbora for looks first and only later discovering how its adult size, behavior, or bioload changes the whole tank plan. Another frequent problem is underestimating its social needs. A token pair or trio often behaves very differently from a real group.

Redline Rasbora Recommended Tank Sizes

Standard aquarium sizes that meet the minimum volume and length requirements for Redline Rasbora.

Show 12 more tank sizes

Frequently Asked Questions About Redline Rasbora

How big does Redline Rasbora get?

Redline Rasbora (Rasbora pauciperforata) typically reaches a maximum adult size of approximately 7 cm. They have a fusiform body shape and a moderate growth rate.

What tank size does Redline Rasbora need?

A minimum aquarium volume of 80 litres and a tank length of at least 80 cm are recommended for Redline Rasbora. This ensures enough swimming space and helps maintain stable water conditions.

What water parameters does Redline Rasbora need?

Redline Rasbora thrives in freshwater only conditions with a temperature range of 22–27°C, a pH between 4 and 6.8, and a general hardness of 1–8 dGH. A low water flow is preferred.

Is Redline Rasbora peaceful or aggressive?

Redline Rasbora is classified as peaceful with an aggression score of 1 out of 10. They are generally well-suited to peaceful community tanks.

How many Redline Rasbora should be kept together?

Redline Rasbora is a schooling species and should be kept in groups of at least 6. Larger groups help distribute aggression and encourage natural schooling behaviour.

Does Redline Rasbora have any special tank requirements?

Yes. Redline Rasbora benefits from leaf litter/blackwater, driftwood (digestion/hiding), plants - densely covered, and plants - floating in the aquarium. These features help replicate their natural habitat and promote overall health and well-being.

Does Redline Rasbora need a lid on the tank?

Yes. Redline Rasbora is a known jumper, and a tight-fitting lid or cover is essential to prevent escape. Even a small gap can be enough for a determined fish to leap out.

Editorial Review

Guidarium Editorial Desk

Reviewed against Guidarium care, stocking, and compatibility standards. Read the editorial policy.

Last reviewed
May 11, 2026
Last updated
May 11, 2026
Issues or corrections?
Contact the editorial team

Top Tank Mates for Redline Rasbora

These fish are strong compatibility matches for Redline Rasbora based on water preferences, temperament, adult size, and tank behavior.

Fish Similar to Redline Rasbora

Blackline Rasbora

Rasbora borapetensis

Cyprinids
6 cm Peaceful

The Blackline Rasbora, often sold as the Red-tailed Rasbora, is a hardy and highly active schooling fish native to Southeast Asia. Recognizable by a bold black lateral line topped with gold and a bright red caudal fin, they are peaceful but energetic. They require plenty of horizontal swimming space in the middle to upper levels of the aquarium and must be kept in schools to feel secure.

Brilliant Rasbora

Rasbora einthovenii

Cyprinids
6.5 cm Peaceful

The Brilliant Rasbora is a peaceful, highly active schooling fish native to the forest streams and peat swamps of Southeast Asia. Known for its shimmering silver body and distinct dark lateral stripe, they thrive in gently flowing, heavily planted blackwater setups with subdued lighting. They are known jumpers, requiring a tight-fitting lid.

Dwarf Rasbora

Boraras maculatus

Cyprinids
2.5 cm Peaceful

A tiny, peaceful shoaling fish native to the blackwater streams and peat swamps of Southeast Asia. Known for their striking red/orange coloration and distinct dark body spots. They are an excellent choice for heavily planted nano tanks and peaceful dwarf shrimp setups. Because of their minute size, they are easily outcompeted for food and predated upon by larger fish.

Chili Rasbora

Boraras brigittae

Cyprinids
2 cm Peaceful

A striking, deeply red nano fish native to the blackwater streams and peat swamps of southern Borneo. They are extremely peaceful and require a mature, densely planted aquarium with soft, acidic water. Due to their tiny size, they are completely safe with adult dwarf shrimp and are ideal for nano setups.

Harlequin Rasbora

Trigonostigma heteromorpha

Cyprinids
4.5 cm Peaceful

A highly popular, peaceful schooling fish recognizable by its metallic copper/orange body and the distinct black triangular 'porkchop' patch on its hindquarters. Originating from peat swamps and blackwater streams in Southeast Asia, they are active swimmers that thrive in heavily planted aquariums with gentle to moderate water flow.

Emerald Eye Rasbora

Brevibora dorsiocellata

Cyprinids
4 cm Peaceful

A small, active schooling fish native to Southeast Asia, famous for the striking black-and-white spot on its dorsal fin and its reflective 'emerald' eyes. They are highly peaceful and thrive in heavily planted or blackwater aquariums. As a strict schooling species, they must be kept in groups to feel secure, establish a natural hierarchy, and display their best colors.