Banggai Cardinalfish (Pterapogon kauderni)

The Banggai Cardinalfish (Pterapogon kauderni) looks like it was designed rather than evolved. A silver body carries three bold black bars, the fins trail into long dramatic points, and the whole thing is dusted with bright white spots that catch the light as it hovers. It moves slowly and deliberately, almost hanging in place, which makes it one of the most watchable fish in a reef tank. Peaceful, hardy, reef safe, and a genuinely good beginner fish once you understand one thing about how they treat each other. Browse the rest of our saltwater livestock and supplies to build the tank around it.

Buy captive bred, and here is why

This species comes from one place on earth: the Banggai Archipelago in Indonesia, a natural range small enough to drive across. Decades of collection for the aquarium trade hit wild populations hard, and in February 2016 NOAA listed the Banggai Cardinalfish as Threatened under the U.S. Endangered Species Act. The good news is that this is one of the easiest marine fish to breed in captivity, so tank bred stock is widely available, better adapted to aquarium life, and takes zero pressure off a fragile wild population. If you are choosing between a wild caught and a captive bred Banggai, it is not a close call.

Care Guide

• Tank size: 30 gallons for one or a pair. Go bigger if you want a group, since the group needs to be large enough to spread aggression around.
• How many, and this is the important part: keep one, keep a bonded pair, or keep six or more in a large tank. What fails is the middle. Three or four Banggai in a normal display will sort themselves into a dominant fish and a victim, and the smallest one gets bullied until it dies. This is the single most common way people lose them.
• Water parameters: 72 to 78°F, pH 8.1 to 8.4, salinity 1.020 to 1.025. Hardy once settled and eating.
• Feeding: carnivore. They are slow, deliberate feeders that will not fight a tang for a mouthful, so target feed if you keep pushy tank mates. PE Mysis and frozen brine are readily taken, and most captive bred fish accept a small pellet like Hikari Marine-S too.
• Shelter: in the wild, juveniles hide among the spines of long-spined urchins and in anemones. A Purple Pincushion Urchin or a bubble tip like our Snowflake Bulb Anemone gives them the same security in a display, though branching rock works fine.
• Flow: moderate at most. These are hoverers, not swimmers, and heavy flow just pushes them around.
• Lid: recommended, as with any reef fish.

Specifications

Compatibility

Peaceful with everything that is not another Banggai, and completely reef safe with corals and inverts including the Scarlet Skunk Cleaner Shrimp. Excellent alongside the Premium Picasso Clownfish, Black Ice Longfin Clownfish, Royal Gramma, Blue Green Chromis, Firefish Goby, Bluestripe Neon Goby, Bicolor Blenny, and the Engineer Goby.

What to watch. Because they feed slowly and hover rather than dart, fast aggressive eaters can quietly starve them out over weeks. It is rarely obvious until the fish is thin. If your tank has pushy feeders, drop food near the Banggai directly rather than trusting it to compete.

Recommended Foods & Supplies

• Piscine Energetics PE Mysis, the staple
• SFBB Mysis Shrimp Cube
• Ocean Nutrition Frozen Brine Shrimp Plus
• Hikari Marine-S small pellet
• Xtreme Marine PeeWee Slow-Sinking Pellets

FAQ

How many should I get?
One, two as a bonded pair, or six or more in a big tank. Never three or four. In small groups they establish a pecking order and the bottom fish gets harassed relentlessly. This is the number one reason Banggai keeping goes wrong, and it is entirely avoidable.

Is it true the males carry the eggs in their mouths?
Yes, and it is one of the best stories in the hobby. The male takes the fertilized eggs into his mouth and broods them for roughly three weeks without eating. There is no free swimming larval stage at all, so what he eventually spits out are tiny, fully formed Banggai Cardinalfish. That quirk is exactly why the species is so straightforward to breed in captivity.

Why does it just hover in one place?
That is normal and it is the charm of the species. Banggai are slow, deliberate hoverers rather than active swimmers. A fish parked in the same corner of the tank is behaving exactly as it should.

Is it legal to buy one?
Yes. The ESA Threatened listing recognizes the pressure on wild populations, but it has not banned trade in the species. Choosing tank bred fish is the meaningful thing you can do, and it is also the better buy since they are already eating prepared food.