Harlequin Rasbora 3-4cm

Available in store

Description

Harlequin Rasbora 3-4cm

A true aquarium classic, the Harlequin Rasbora combines warm copper-orange colouration with its unmistakable black triangular “harlequin” marking. Peaceful, hardy and highly social, Trigonostigma heteromorpha is an excellent schooling fish for planted community aquariums and remains one of the best Rasboras for both newer and experienced fish keepers.

Quick Facts

  • Brand: AI Livestock
  • Product type: Rasboras
  • Size / Capacity: 4cm
  • Suitable for: Species-appropriate, established aquariums
  • SKU: 26025

Is this for you?

✔️ Perfect if:

  • Your aquarium is fully cycled and stable.
  • Adult size, social needs and compatibility have been checked.
  • You can provide the correct water conditions, diet and habitat.
  • You can receive and acclimate live livestock promptly.

❌ Consider something else if:

  • The aquarium is new, uncycled or unstable.
  • Compatibility or long-term space has not been confirmed.
  • You cannot meet the species-specific husbandry requirements.

Why choose Harlequin Rasbora 3-4cm?

It provides a clearly identified livestock option that can be assessed against your aquarium.

Matching adult size, behaviour and water needs helps prevent avoidable stress.

A planned addition is easier to acclimate, feed and monitor.

It is preferable to a similar-looking species when its long-term needs better suit your setup.

Key Benefits

  • Planned selection – Supports matching livestock to a suitable aquarium.
  • Aquarium suitability – Can become a rewarding part of a properly planned community.
  • Clear checks – Encourages confirmation of size, water and compatibility.
  • Long-term care – Keeps husbandry ahead of impulse selection.
  • Specialist support – NTA can help clarify suitability before ordering.

Specifications

  • Capacity / Size: 4cm
  • SKU: 26025
  • Shopify category: Live Animals

Specifications may vary by model or manufacturer revision. Please check the selected variant where applicable.

What's included?

  • The selected live livestock variant.
  • Protective packing appropriate to the available fulfilment method.
  • Care or acclimation guidance where supplied.
  • Only items explicitly stated in the listing are included.

Setup & Use

  1. Prepare and test the aquarium before arrival.
  2. Inspect the package and follow current NTA acclimation guidance.
  3. Introduce the livestock calmly with reduced lighting where appropriate.
  4. Observe behaviour and compatibility closely.
  5. Maintain stable water and feed an appropriate diet.

Maintenance

Regular inspection and appropriate care help keep this product or livestock in suitable condition.

  • Test water regularly.
  • Maintain stable, species-appropriate parameters.
  • Feed controlled portions of a suitable diet.
  • Monitor growth, behaviour and compatibility.

Pairs perfectly with

  • A reliable water test kit.
  • Species-appropriate food.
  • Water conditioner.
  • Suitable plants, caves or cover.
  • A quarantine or observation setup where appropriate.
NTA Insight:
Check the adult animal, not only the size offered today. Adult size, social needs and behaviour are often the deciding factors.

Before You Buy

Compatibility: Confirm the exact product, variant, livestock and system compatibility before ordering.

Sizing: Use verified dimensions, actual aquarium volume and the intended application rather than relying on appearance alone.

Installation: Check access, placement, connections and safe operating requirements before use.

Replacement parts: Availability varies by product and manufacturer; confirm the exact model or SKU when a replacement is essential.

FAQ

How large do Harlequin Rasboras grow?

Adults generally reach approximately 4–5 cm, making them larger and more substantial than tiny species such as Chilli and Phoenix Rasboras.

How many Harlequin Rasboras should I keep?

Keep at least six, although we strongly prefer groups of ten or more where aquarium size allows. Larger groups generally produce more confident and natural behaviour.

Are Harlequin Rasboras schooling fish?

Yes. They are highly social fish and should be maintained as a group. They may form a relatively loose school when relaxed and tighten their grouping when disturbed.

Are Harlequin Rasboras suitable for beginners?

Yes. They are one of the more reliable small community fish and are an excellent choice once the aquarium is properly cycled and stable.

Are Harlequin Rasboras aggressive?

No. They are peaceful community fish. Males may display towards one another, but serious aggression is unusual.

What should I feed them?

Quality flakes or appropriately sized micro pellets make excellent staple foods. Supplement these with frozen or live foods such as brine shrimp and daphnia for variety and conditioning.

How can I tell males and females apart?

Mature females are generally fuller and deeper-bodied, particularly when carrying eggs. Males often remain slimmer and may display stronger colour. Sexing young fish can be difficult.

Can Harlequin Rasboras live with Bettas?

Potentially. Harlequins are peaceful and generally suitable community fish, but individual Betta temperament varies. Provide sufficient aquarium space, plants and visual cover, and monitor the fish carefully.

What does Harlequin Rasbora 3-4cm do?

Harlequin Rasbora 3-4cm is intended for species-appropriate, established aquariums. Check the selected option and listing details against your needs.

What aquarium size is it suitable for?

Use any verified rating in the Specifications section as a starting point. If no rating is stated, contact NTA when tank size is the deciding factor.

Is this the right model for my aquarium?

Confirm purpose, physical fit, capacity and compatibility before ordering.

What's included in the box?

Only the selected product and components explicitly stated in the current listing are included.

Harlequin Rasbora 3-4cm

Available in store

Product form

SKU: 26025

Out of stock,  

$7.00


All prices include GST
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    Description

    Harlequin Rasbora 3-4cm

    A true aquarium classic, the Harlequin Rasbora combines warm copper-orange colouration with its unmistakable black triangular “harlequin” marking. Peaceful, hardy and highly social, Trigonostigma heteromorpha is an excellent schooling fish for planted community aquariums and remains one of the best Rasboras for both newer and experienced fish keepers.

    Quick Facts

    • Brand: AI Livestock
    • Product type: Rasboras
    • Size / Capacity: 4cm
    • Suitable for: Species-appropriate, established aquariums
    • SKU: 26025

    Is this for you?

    ✔️ Perfect if:

    • Your aquarium is fully cycled and stable.
    • Adult size, social needs and compatibility have been checked.
    • You can provide the correct water conditions, diet and habitat.
    • You can receive and acclimate live livestock promptly.

    ❌ Consider something else if:

    • The aquarium is new, uncycled or unstable.
    • Compatibility or long-term space has not been confirmed.
    • You cannot meet the species-specific husbandry requirements.

    Why choose Harlequin Rasbora 3-4cm?

    It provides a clearly identified livestock option that can be assessed against your aquarium.

    Matching adult size, behaviour and water needs helps prevent avoidable stress.

    A planned addition is easier to acclimate, feed and monitor.

    It is preferable to a similar-looking species when its long-term needs better suit your setup.

    Key Benefits

    • Planned selection – Supports matching livestock to a suitable aquarium.
    • Aquarium suitability – Can become a rewarding part of a properly planned community.
    • Clear checks – Encourages confirmation of size, water and compatibility.
    • Long-term care – Keeps husbandry ahead of impulse selection.
    • Specialist support – NTA can help clarify suitability before ordering.

    Specifications

    • Capacity / Size: 4cm
    • SKU: 26025
    • Shopify category: Live Animals

    Specifications may vary by model or manufacturer revision. Please check the selected variant where applicable.

    What's included?

    • The selected live livestock variant.
    • Protective packing appropriate to the available fulfilment method.
    • Care or acclimation guidance where supplied.
    • Only items explicitly stated in the listing are included.

    Setup & Use

    1. Prepare and test the aquarium before arrival.
    2. Inspect the package and follow current NTA acclimation guidance.
    3. Introduce the livestock calmly with reduced lighting where appropriate.
    4. Observe behaviour and compatibility closely.
    5. Maintain stable water and feed an appropriate diet.

    Maintenance

    Regular inspection and appropriate care help keep this product or livestock in suitable condition.

    • Test water regularly.
    • Maintain stable, species-appropriate parameters.
    • Feed controlled portions of a suitable diet.
    • Monitor growth, behaviour and compatibility.

    Pairs perfectly with

    • A reliable water test kit.
    • Species-appropriate food.
    • Water conditioner.
    • Suitable plants, caves or cover.
    • A quarantine or observation setup where appropriate.
    NTA Insight:
    Check the adult animal, not only the size offered today. Adult size, social needs and behaviour are often the deciding factors.

    Before You Buy

    Compatibility: Confirm the exact product, variant, livestock and system compatibility before ordering.

    Sizing: Use verified dimensions, actual aquarium volume and the intended application rather than relying on appearance alone.

    Installation: Check access, placement, connections and safe operating requirements before use.

    Replacement parts: Availability varies by product and manufacturer; confirm the exact model or SKU when a replacement is essential.

    FAQ

    How large do Harlequin Rasboras grow?

    Adults generally reach approximately 4–5 cm, making them larger and more substantial than tiny species such as Chilli and Phoenix Rasboras.

    How many Harlequin Rasboras should I keep?

    Keep at least six, although we strongly prefer groups of ten or more where aquarium size allows. Larger groups generally produce more confident and natural behaviour.

    Are Harlequin Rasboras schooling fish?

    Yes. They are highly social fish and should be maintained as a group. They may form a relatively loose school when relaxed and tighten their grouping when disturbed.

    Are Harlequin Rasboras suitable for beginners?

    Yes. They are one of the more reliable small community fish and are an excellent choice once the aquarium is properly cycled and stable.

    Are Harlequin Rasboras aggressive?

    No. They are peaceful community fish. Males may display towards one another, but serious aggression is unusual.

    What should I feed them?

    Quality flakes or appropriately sized micro pellets make excellent staple foods. Supplement these with frozen or live foods such as brine shrimp and daphnia for variety and conditioning.

    How can I tell males and females apart?

    Mature females are generally fuller and deeper-bodied, particularly when carrying eggs. Males often remain slimmer and may display stronger colour. Sexing young fish can be difficult.

    Can Harlequin Rasboras live with Bettas?

    Potentially. Harlequins are peaceful and generally suitable community fish, but individual Betta temperament varies. Provide sufficient aquarium space, plants and visual cover, and monitor the fish carefully.

    What does Harlequin Rasbora 3-4cm do?

    Harlequin Rasbora 3-4cm is intended for species-appropriate, established aquariums. Check the selected option and listing details against your needs.

    What aquarium size is it suitable for?

    Use any verified rating in the Specifications section as a starting point. If no rating is stated, contact NTA when tank size is the deciding factor.

    Is this the right model for my aquarium?

    Confirm purpose, physical fit, capacity and compatibility before ordering.

    What's included in the box?

    Only the selected product and components explicitly stated in the current listing are included.

    Live Arrival & Ordering FAQ

    Why do livestock prices sometimes change?

    Unlike manufactured products, fish and shrimp continue to grow and develop over time. Their value changes as they increase in size, develop colour, or become breeding pairs.

    Our prices are based on the current size, quality and availability of each specimen. While pricing often remains stable for around 3–4 months, it may be updated at any time to reflect these changes.

    We always aim to offer healthy, high-quality livestock at fair and competitive prices.

    Do you offer a live arrival guarantee?

    Yes. All livestock is covered by our Live Arrival Guarantee.

    In the rare event of DOA, please contact us promptly with clear photos of the livestock in the original unopened bag.

    Please review our full DOA and store policies before purchase.

    Can you ship to all states in Australia?

    No. Due to state restrictions, we cannot ship livestock or live plants to WA and TAS.

    What should I check before ordering?

    Before placing an order, make sure:

    • Your tank is fully cycled and stable
    • Your aquarium has enough space for the species
    • Your current livestock are compatible in temperament, size, and requirements
    • Your water parameters, habitat, and temperature suit the species
    • You are not adding too many fish at once
    What should I expect when my fish arrives?

    It is normal for fish, shrimp, or snails to look pale, stressed, or less active after shipping.

    This is temporary. Most livestock will settle and regain colour within a few days.

    How long does it take for fish to settle in?

    Most livestock will take 3–7 days to fully adjust to their new environment.

    Should I feed my fish immediately after arrival?

    No. We recommend waiting 24 hours before feeding to allow them to settle.

    If you already have fish in your tank, feeding them before introducing new arrivals can help reduce stress.

    Why do fish sometimes struggle after being added to a tank?

    In most cases, issues are caused by tank conditions, not shipping.

    • Uncycled or unstable tanks
    • Poor water parameters
    • Overstocking
    • Unsuitable tank mates
    What is Nano Tanks Australia’s main tip for new livestock?

    Most livestock losses happen in immature or unstable tanks, not during shipping.

    If your setup is not fully established, the risk to new arrivals is significantly higher.

    Not sure if this fish is right for your setup?

    If you are unsure whether this species suits your setup, contact us before ordering and we’ll help point you in the right direction.

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