Banggai Cardinalfish
Pterapogon kauderni
Striped cardinalfish best bought captive-bredIntermediate
- Lifespan
- 4-5 years
- Size
- 8 cm (3 in)
- Social needs
- Pair or small group with ample space
- Time
- Daily feeding; weekly testing/changes
- Cost
- Medium
- Diet
- Carnivore (mysis, brine, copepods, frozen)
Overview
What is this animal?
- The Banggai Cardinalfish is a silver fish with bold black bars and white-spotted fins.
- Endemic to a small range in Indonesia, wild populations are threatened by overcollection, so buying captive-bred stock is the more ethical and hardier choice.
- Captive-bred fish adapt readily and ship far better than wild ones.
- These are mouthbrooders: the male incubates eggs and fry in his mouth, making them one of the more readily bred marine fish at home.
- Slow-moving and peaceful, they hover in the open and add contrast to a reef.
Temperament
- Banggai are peaceful and reef-safe toward other species but can be aggressive among themselves.
- As juveniles mature in a group they pair off and harass the remaining fish, so keep a single individual or an established male-female pair.
- They hover slowly in the open, often near branching cover, and pose no threat to corals or most invertebrates.
- With careful stocking they are calm fish whose unusual breeding behaviour rewards attentive keepers.
A good fit for
- Keepers wanting to breed marine fish
- Ethical buyers choosing captive-bred
- Peaceful reef community tanks
- Aquarists who enjoy calm, hovering fish
Common mistakes to avoid
- Buying wild-caught (threatened, poor survival)
- Crowding juveniles - they bully as they pair
- Slow feeders outcompeted by fast tankmates
- Too-small tank causing aggression
Enclosure
Minimum 110 litres (29 US gallons) — for the pair
Cannot be kept alone. The minimum is 2, and the space above is for that group.
- A cycled 110L (30 gal) tank suits a pair; larger groups need more space and many sight-line breaks to prevent bullying.
- Keep salinity 1.024-1.026, temperature 23-27°C (74-80°F), pH 8.1-8.4, and nitrate low.
- Long-spined urchins or branching corals give fry natural shelter.
- A tight lid is advisable.
- Stable water and ample structure reduce in-group aggression and give this slow, deliberate fish the calm environment it prefers in order to thrive and even breed.
Supplies
Setup
- Tank, stand and sump
- Return pump and powerheads
- Protein skimmer
- Reef lighting
- Rock and sand
- Salt mix, refractometer and test kits
- Quarantine tank
Ongoing
- Frozen mysis shrimp
- Frozen enriched brine shrimp
- Frozen or live copepods
- Small marine pellets
- Vitamin or HUFA soaking supplement
- Turkey baster for target-feeding
- Small thawing cup and strainer
Safe substrate: Aragonite sand · Dry or cured live rock · Bare bottom
Care routine
Daily
- Check salinity, temperature and flow
- Head-count and look everyone over
- Several small feeds a day
- Top up evaporation with fresh water
Weekly
- Service the skimmer and filter socksevery 3 days
- Clean the glass
- Test the water
Monthly
- Water changeevery 2 weeks
- Calibrate the refractometer
- Check salt, RO/DI and reagents
Less often
- Deep-clean pumps and powerheadsevery 3 months
- Replace RO/DI filter mediaevery 6 months
Vet: Quarterly condition review — every 3 months
Top resources for more info
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Diet
- The Banggai is a carnivore that can be a slow, picky eater.
- Offer enriched frozen mysis and brine shrimp, copepods, and small marine pellets, fed once or twice daily.
- Vitamin-soaked foods improve condition and breeding success.
- Because they feed deliberately, make sure faster tankmates do not strip the food before they eat.
- Target-feeding shy individuals helps.
- A varied meaty diet keeps them in good weight, which is important for successful mouthbrooding.
Health
- Captive-bred Banggai are reasonably hardy, but the species is prone to a specific Iridovirus and to stress-related disease, especially in poorly acclimated wild fish.
- Buying captive-bred and quarantining new arrivals greatly reduces risk.
- Watch for slow feeding, emaciation, rapid breathing, or white spots.
- Keep nitrate low and parameters stable, and avoid crowding, which causes chronic stress.
- Well-fed, uncrowded fish in clean water generally stay healthy through their lifespan.
Is your enclosure big enough?
Is this urgent?
In a reef, stability matters more than any single target number. A parameter moving fast does more damage than a parameter sitting slightly off.
Go now
Today
Quarantine every new animal, including corals and inverts. It is the single practice that separates a reef that lasts from a reef that restarts.
This is general guidance for a healthy adult, not a diagnosis. An exotics vet who knows your animal always overrides it — and the time to find one is before you need one.
What it really costs
Setup, monthly, first year and across a whole life, itemised and with the electricity worked out from the actual wattage. Published figures for the same animal disagree by a factor of four, so the calculator shows ranges rather than picking one.
Bedding and substrate
In a marine system the rock and the sand are life support, and how you start them decides the first six months.
Safe
With a caveat
Never
This is our general list for saltwater fish. We have not built one specific to Cardinalfish yet.
My kit says 0.25 ppm. Is that dangerous?
A liquid kit measures total ammonia, but only the un-ionised fraction is really toxic, and that fraction is governed by pH and temperature — each whole pH unit multiplies it roughly tenfold. So the same reading can be nearly harmless in one tank and lethal in another; this works out which one you are in.
Compare with other animals
The same axes for every animal, side by side — the way the guides are written makes that a fair comparison rather than two articles.
Cardinalfish, side by side
Same axes, same care guides — the honest way to choose between types.
See all Cardinalfish side by side →
