Cardinalfish

Banggai cardinalfish

Pterapogon kauderni

Also sold as Kaudern's cardinal, Longfin cardinalfish

Good first fish

Banggai cardinalfish (Pterapogon kauderni), photographed in the sea or an aquarium — Photo: Rickard Zerpe, CC BY 2.0, via Wikimedia Commons

Care level: Beginner
Adult size: 7.6 cm in aquariums
Minimum tank: 114 litres
Temperament: Mostly peaceful
With corals: Reef safe
Captive-bred: Widely sold captive-bred
IUCN status: Endangered

Show volumes inLitresUK gallonsUS gallons

How do you care for the banggai cardinalfish?

Semi-aggressive towards its own kind; peaceful to others.

Feeding

Carnivore.

Captive-bred fish eat frozen and pellet foods.

Tank and special needs

Plan for at least 114 litres of water (the care sheet says 30 US gallons).

Calm water areas; likes long-spined urchins or branching coral to hover by.

Why this care level

Captive-bred only; wild fish are not beginner fish because of import losses.

Corals and invertebrates

None.

Which tankmates suit the banggai cardinalfish?

Do not keep large groups; pairs or a single fish. Males mouthbrood.

Suggested order in a mixed tank: add after the first peaceful fish.

More than one banggai cardinalfish

Only as a mated pair, or two juveniles added together. A third banggai cardinalfish is usually driven out.

Other fish

Checked against the other 59 fish in this guide, assuming a tank big enough for both. Individual fish differ, so treat this as a starting point.

Usually fine together (59)

Invertebrates

Only the invertebrates with a known risk are listed.

Take care (2)

Tiger tail sea cucumberA stressed or dead tiger tail sea cucumber can release toxins that harm fish; cover pump intakes.
Sea appleA stressed or dead sea apple can release toxins that harm fish; cover pump intakes.

Corals and anemones

Only the corals and anemones with a known risk are listed.

Take care (1)

Carpet anemones (Haddon's, giant)The carpet anemones (Haddon's, giant) can catch and eat small fish such as the banggai cardinalfish.

These checks follow the reasons fish and invertebrates clash: same species or genus, similar shape, mouth size, temperament, food, burrows, tank size and the order they are added. Individual animals differ; every source agrees on that.

Quarantine and health

Wild-caught imports have suffered iridovirus outbreaks with reported losses over 50% within 4 to 6 weeks (trade reports). typical, check

New fish are the most common way disease gets into a reef tank. Quarantine every fish in a separate tank before it joins the display, and choose a method that suits its tolerance of copper.

Captive-bred or wild?

Bred at scale (one Thai farm reported over 100,000 a year; TMC in the UK has supplied captive-bred fish). Endangered on the IUCN Red List; buy captive-bred only.

IUCN Endangered; wild population reported much reduced by collection. A CITES Appendix II listing was proposed in 2007 and not adopted, and the species was discussed again around the 2016 CITES meeting (outcome not confirmed); the US listed it as threatened under the Endangered Species Act (2016). typical, check

What does it cost in the UK?

about £24. This is one UK retailer’s listing on 21 October 2026, not a market average, and every item was sold out on that day.

Sources

LiveAquaria (US retailer) care sheetRead 21 October 2026, read in full. Used for: stats.
FishBase species summaryRead 21 October 2026, read in full. Used for: max length, IUCN EN.
Reef Builders articleRead 21 October 2026, search summary only. Used for: ESA listing.
Practical Fishkeeping (UK) articleRead 21 October 2026, search summary only. Used for: UK captive-bred supply.
Microcosm Aquarium Explorer entryRead 21 October 2026, search summary only. Used for: iridovirus, captive-bred advice.
Kraken Corals (UK retailer) catalogueRead 21 October 2026, read in full. Used for: UK price.

Last checked 21 October 2026. How we check

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