TankBud

Banggai cardinalfish

Pterapogon kauderni

Also known as Kaudern's Cardinalfish, Kaudern's Cardinal, Longfin Cardinalfish

SaltwaterFish

Banggai cardinalfish (Pterapogon kauderni)
Rickard Zerpe · CC BY 2.0

Care at a glance

Temperature
73–82°F
23–28°C
pH
8.1–8.4
Adult size
3.1 in
8 cm
Minimum tank
29 gal
110 L
Temperament
Mostly peaceful
Social behavior
Social
Swim level
Middle
Diet
Carnivore
Difficulty
Easy
Breeding
Mouthbrooder · Easy
Rarity
Common
Reef safe
Reef safe
Family
Apogonidae
Origin
Banggai Islands, Indonesia (western central Pacific)

Overview

The Banggai cardinalfish is a mostly peaceful, reef-safe fish that hovers near cover in the middle of the tank. It is easy to keep and easy to breed.

Did you know

Banggai young develop in the father's mouth with no drifting larval stage, so wild Banggai never spread far from their home islands.

Caring for the Banggai cardinalfish

Keep Banggai cardinalfish in a well-established tank of at least 29 gal (110 L), with plenty of live rock and open swimming lanes. They are slow, deliberate swimmers that hang in the middle of the water near cover.

Hold the water at 73 to 82°F (23 to 28°C) and a pH of 8.1 to 8.4. Banggai are carnivores and want small meaty foods such as mysis and enriched brine shrimp. Choose calm, slow tank mates so they are not outcompeted at feeding time.

The Banggai cardinalfish is reef safe and will not touch corals or sessile invertebrates, though a large adult may snap up very small ornamental shrimp. You can keep one singly, as a bonded pair, or as a small group in a larger tank. A settled pair often turns territorial and harasses other Banggai that stray too close.

The male is a mouthbrooder. He holds the eggs, and then the fully formed young, in his mouth for around three to four weeks. He releases miniature fish rather than free-swimming larvae, which is one reason Banggai breed so readily in captivity.

Good to know

The Banggai cardinalfish, Pterapogon kauderni, is a cardinalfish in the family Apogonidae. It is also sold as Kaudern's cardinalfish or the longfin cardinalfish. It is listed as Endangered on the IUCN Red List and was proposed for CITES protection. Buying captive-bred stock takes pressure off the wild populations.

In the wild

Banggai cardinalfish come from a tiny cluster of islands in Indonesia, in the western central Pacific. They shelter in seagrass beds and among branching corals. Juveniles famously hide among the spines of long-spined sea urchins.

Symbiotic relationships

Banggai cardinalfish and the long-spine urchin

Banggai cardinalfish hover in small groups among the spines of long-spine urchins, and the young go deeper into the spines than the adults. The spines are long, brittle and venomous enough that predators leave the urchin alone, which makes the space between them a nursery. The fish are so tied to their shelter that a group rarely strays more than a few yards from it. The urchin gets nothing obvious in return.

Add a long-spine urchin to a mature tank with plenty of rock and algae for it to graze, at the tank size its own profile lists, and a group of Banggai will settle over it within days, drifting through the spines exactly as they do on the reef. The spines break off in skin, so keep hands and nets clear. Banggai cardinalfish are endangered in the wild: they have a tiny range, never disperse from their home reefs, and were collected heavily for the trade. Buy captive-bred fish, which are widely available.

Every symbiotic relationship in the catalog

Weekly picks

Tank mates

The Banggai cardinalfish is a mostly peaceful, social species that keeps to the middle. These picks share a community profile with it, are safe together in both directions, and overlap on water type, temperature and pH.

Check the full mix in the stocking calculator

Common questions

What size tank does a Banggai cardinalfish need?

A Banggai cardinalfish needs at least 29 gal (110 L). It spends most of its time in the middle.

What temperature and pH does a Banggai cardinalfish need?

A Banggai cardinalfish is comfortable at 73–82°F (23–28°C) with a pH of 8.1–8.4.

What does a Banggai cardinalfish eat?

A Banggai cardinalfish is a carnivore. It eats small meaty foods such as mysis and enriched brine shrimp.

How big does a Banggai cardinalfish get?

An adult Banggai cardinalfish reaches about 3.1 in (8 cm).

How does a Banggai cardinalfish breed?

Banggai cardinalfish are mouthbrooders. The male carries the eggs, then the fully formed young, in his mouth for about three to four weeks. He releases miniature fish, and Banggai breed readily in captivity.

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