Banggai Cardinalfish Care Guide

Pterapogon kauderni

Minimum Tank Size30 Gallons
Water Parameters74-82 F, pH 8.1-8.4, Salinity 1.022-1.025

Banggai Cardinalfish bring a different look to the salt water environment. They do not swim around rapidly like wrasse nor wiggle around like clowns. Instead they enjoy floating in place, making short dashing motions rather than slow continuous movements. This gives them an almost decorative look in the tank as they hang around their favorite spots.

The Banggai Cardinalfish is typically rated as semi-aggressive however this will mostly apply to other cardinalfish only. Only keep multiple Banggai Cardinalfish if they are opposite genders or if you have a large tank that will give them all plenty of territory.

The Banggai Cardinalfish is currently borderline endangered due to collection. Be sure to ask your local fish store where the fish come from and try to buy captive bred fish whenever possible.


banggai cardinalfish

The Banggai Cardinal fish is reef friendly and does not typically harass other fish. They also will not attack inverts, making them an ideal fish for new saltwater enthusiasts. While they are typically kept in large schools in stores, this is not recommended in the home aquarium as they will fight one another in almost all cases. A single mated pair should be the goal of most home aquariums.

The Banggai Cardinalfish is found in shallow areas of the water surrounding the Banggai islands of Indonesia. Banggai cardinalfish will form relationships with sea urchins, anemones and branching corals, allowing for interesting interactions in the home tank. When disturbed the Banggai Cardinalfish will retreat back to the sea urchin or its place of safety. Their still nature also encourages any near by cleaner shrimp, making them excellent tank mates.

When Banggai Cardinalfish are faced with others of the same gender in a small area they will often flare their fins at one another to give a warning. Because neither of the fish can leave the other in a tank, fighting/harassment will almost always occur after flaring has been observed. If you see your cardinalfish fighting or chasing one another I highly advise you to separate them with either a in tank net basket or place them in different tanks entirely. If the fish cannot be kept together it is highly advised to return all but a mated pair, as they will continue to harass one another until only one or one mated pair remains.

Diet & Feeding

The Banggai Cardinal fish feeds mainly off copepods in the wild. In the home aquarium they can be slow to accept pellet or flake food but should take live or frozen foods right away. The majority of Banggai Cardinalfish will adapt to eating prepared foods once they recognize you as their feeder and understand when feeding time is. Keeping the cardinalfish with other fish will speed up this process, as they will all feed at the same time and help one another notice the food.


As previously stated the Banggai Cardinalfish will not be aggressive to other fish in normal circumstances. They will however be aggressive to their own kind when not given enough space for different territories. You may keep two Banggai Cardinalfish in a small tank if they are a mated pair.

Aggression from this fish is easy to spot, as their large fins make any flaring easy to spot. Likewise their usual calm floating swim patterns will become far more aggressive if they are angry with another fish. They will also flare their gills when fed or during mating, so be sure they are being aggressive and not behaving normally before removing them.

Sexing & Breeding

Their are no visible difference between male and female Banggai Cardinalfish. Though this fish are indeed mouth brooding fish, meaning the male will keep the eggs in their mouths until they spawn, the males jaw is no bigger than the females. This makes sexing almost impossible. Currently the best method for Sexing Banggai Cardinalfish, developed by Wolfgang Mai, is to feed them excessively so that their stomach bulge outwards. Then view the bottom of the fish and look between their pelvic and anal fins. The Banggai Cardinalfish will have white triangle shaped vents there. Females will have one vent while males will have two vents. The only difficulties this method presents is feeding shy fish excessive amounts. This means you should perform this check in an isolation tank before adding the cardinalfish to the main tank.

The Banggai Cardinalfish will begin breeding after they have become acclimated in the tank. This can take a few months, as they often take awhile to get used to new food sources, water conditions and other fish in the tank. Making sure the water parameters are as good as possible should help speed the process up. You must also ensure no other fish are harassing them as they will not breed under stress.

Once the fish are comfortable you should begin slightly overfeeding them, building up their energy and comfort. Most fish will not spawn if they are unsure about how much food they can get. maintaining good water conditions and feeding the fish at consistent times should ensure breeding.

Once the pair breeds the male will suppress his appetite and carry the eggs in his mouth, giving him a large goofy looking jaw. Remove the male from the main tank and place him into a separate tank in which you can raise the fry. Do not stress the male too much when catching him. The fry will typically hatch after twenty days so you do not have to rush on catching the male. Be sure your fry raising tank is in good conditions before placing the male in there.

As the fry spawn they will come out of the males mouth until he has no more eggs. He will then move his jaw line back to normal and begin searching for food. Because he is in the breeder tank with only his fry he may look to eat them. Typically the father will seek out the naupli before he turns to the fry. Remove him and feed him right away.

The fry should be fed twice a day with one day old brine shrimp naupli. If you breed fish often it is suggested you keep a brine shrimp hatchery, as both tanks and fry love live brine shrimp. Fry will reach juvenile state around two months later and can be added to the main tank, provided their are no fish hunting predators. If there are some of these, such as hawkfish, you may want to wait until the cardinalfish are an inch and a half or larger before adding them to the main tank. Additionally do not add they fry to the same tank as their parents, as you will create conflicting genders and therefore fighting.

2 thoughts on “Banggai Cardinalfish Care Guide”

  1. We have a 10 gallon tank with two hermit crabs, and we are planning on adding a clownfish and a Banggai cardinalfish. We were wondering whether or not it’d be okay to keep only a single Banggai cardinalfish because we’ve read other websites that recommended we keep them individually or as bonded pairs, but when we went to buy one, a salesperson advised against it, saying we have to buy at least two. Is this true, or would one be fine?

    • Plenty of people will keep these fish solo. There is no big issue with it and getting a pair is not as easy as other fish, as they do not change genders. This means if you happen to buy two males they will eventually fight to the death. You can find out their gender but for a 10 gal I would just stick to the one cardinalfish.


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