Red Dwarf Pencilfish (Nannostomus mortenthaleri)

Available in store

Description

Red Dwarf Pencilfish (Nannostomus mortenthaleri)

Red Dwarf Pencilfish (Nannostomus mortenthaleri) brings slender body form and detailed group display to a suitably prepared aquarium. Plan its home around adult space, water, diet and social needs rather than the current sale size.

Quick Facts

  • Scientific name: Nannostomus mortenthaleri
  • Product type: small schooling pencilfish
  • Sale unit: One individual per quantity ordered unless the listing states otherwise
  • Social needs: Social fish best kept in an appropriate group; males may display to each other

Is this for you?

Perfect if: you can keep a group with peaceful companions and appropriately small foods.

Consider something else if: the tank contains large, aggressive or highly competitive feeders.

Why choose Red Dwarf Pencilfish (Nannostomus mortenthaleri)?

Choose Red Dwarf Pencilfish (Nannostomus mortenthaleri) for slender body form and detailed group display. Base compatibility and long-term housing on its adult requirements; individual appearance and maturity can vary.

Key Benefits

  • Slender body form and detailed group display
  • Husbandry guidance focused on small schooling pencilfish needs
  • Clear sale-size and sale-unit information for purchase planning

Care & Specifications

Use a mature, covered planted aquarium with shaded areas, gentle flow and calm companions.

Social requirements: Social fish best kept in an appropriate group; males may display to each other.

What will you receive?

You will receive the selected quantity of Red Dwarf Pencilfish (Nannostomus mortenthaleri). Size within the stated range, colour, markings, finnage and sex can vary between individuals unless the listing explicitly fixes them.

Acclimation & Introduction

Prepare the small schooling pencilfish aquarium before arrival and follow current NTA livestock acclimation guidance. Reduce lighting, avoid sudden changes in temperature or water chemistry, and monitor breathing, posture, feeding and interactions after introduction.

Ongoing Care

Offer fine prepared food with very small frozen or live foods, making sure all fish feed.

Maintain stable water through testing and appropriately sized water changes. Review the setup as Red Dwarf Pencilfish (Nannostomus mortenthaleri) grows or social behaviour changes.

Pairs perfectly with

  • A mature aquarium prepared for this livestock
  • Reliable water tests and species-appropriate filtration
  • Food selected for the animal’s mouth size and feeding zone
NTA Insight:
Pencilfish often look their best when they feel secure enough to display. Cover and a calm feeding environment matter more than strong lighting.

Before You Buy

Check the adult size, social structure, water requirements and diet for Red Dwarf Pencilfish (Nannostomus mortenthaleri) before ordering. The listed sale size describes current stock, not its permanent size.

Compatibility lists are guides only. Individual behaviour, aquarium dimensions, sex, group size and established territories can change the outcome.

FAQ

Should pencilfish be kept alone?
No. Plan an appropriate group and enough planted cover for natural social display.

Will the supplied Red Dwarf Pencilfish (Nannostomus mortenthaleri) match the photograph exactly?
No. Livestock photographs represent the species or variety; colour, markings, finnage, size and maturity naturally vary.

Is the listed size the adult size?
No. It is an approximate sale size where stated. Confirm adult requirements before purchase.

Red Dwarf Pencilfish (Nannostomus mortenthaleri)

Available in store

Product form

Out of stock

$80.00  $40.00


All prices include GST
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    Description

    Red Dwarf Pencilfish (Nannostomus mortenthaleri)

    Red Dwarf Pencilfish (Nannostomus mortenthaleri) brings slender body form and detailed group display to a suitably prepared aquarium. Plan its home around adult space, water, diet and social needs rather than the current sale size.

    Quick Facts

    • Scientific name: Nannostomus mortenthaleri
    • Product type: small schooling pencilfish
    • Sale unit: One individual per quantity ordered unless the listing states otherwise
    • Social needs: Social fish best kept in an appropriate group; males may display to each other

    Is this for you?

    Perfect if: you can keep a group with peaceful companions and appropriately small foods.

    Consider something else if: the tank contains large, aggressive or highly competitive feeders.

    Why choose Red Dwarf Pencilfish (Nannostomus mortenthaleri)?

    Choose Red Dwarf Pencilfish (Nannostomus mortenthaleri) for slender body form and detailed group display. Base compatibility and long-term housing on its adult requirements; individual appearance and maturity can vary.

    Key Benefits

    • Slender body form and detailed group display
    • Husbandry guidance focused on small schooling pencilfish needs
    • Clear sale-size and sale-unit information for purchase planning

    Care & Specifications

    Use a mature, covered planted aquarium with shaded areas, gentle flow and calm companions.

    Social requirements: Social fish best kept in an appropriate group; males may display to each other.

    What will you receive?

    You will receive the selected quantity of Red Dwarf Pencilfish (Nannostomus mortenthaleri). Size within the stated range, colour, markings, finnage and sex can vary between individuals unless the listing explicitly fixes them.

    Acclimation & Introduction

    Prepare the small schooling pencilfish aquarium before arrival and follow current NTA livestock acclimation guidance. Reduce lighting, avoid sudden changes in temperature or water chemistry, and monitor breathing, posture, feeding and interactions after introduction.

    Ongoing Care

    Offer fine prepared food with very small frozen or live foods, making sure all fish feed.

    Maintain stable water through testing and appropriately sized water changes. Review the setup as Red Dwarf Pencilfish (Nannostomus mortenthaleri) grows or social behaviour changes.

    Pairs perfectly with

    • A mature aquarium prepared for this livestock
    • Reliable water tests and species-appropriate filtration
    • Food selected for the animal’s mouth size and feeding zone
    NTA Insight:
    Pencilfish often look their best when they feel secure enough to display. Cover and a calm feeding environment matter more than strong lighting.

    Before You Buy

    Check the adult size, social structure, water requirements and diet for Red Dwarf Pencilfish (Nannostomus mortenthaleri) before ordering. The listed sale size describes current stock, not its permanent size.

    Compatibility lists are guides only. Individual behaviour, aquarium dimensions, sex, group size and established territories can change the outcome.

    FAQ

    Should pencilfish be kept alone?
    No. Plan an appropriate group and enough planted cover for natural social display.

    Will the supplied Red Dwarf Pencilfish (Nannostomus mortenthaleri) match the photograph exactly?
    No. Livestock photographs represent the species or variety; colour, markings, finnage, size and maturity naturally vary.

    Is the listed size the adult size?
    No. It is an approximate sale size where stated. Confirm adult requirements before purchase.

    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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