The Black and White Heniochus is often called the “Poor Man’s Moorish Idol”… but we are tempted to call it the “Sane Man’s Moorish Idol”!

The Black and White Heniochus Heniochus acuminatus is a real eye-catcher. This is a graceful butterflyfish with a beautiful and unusual appearance. It’s a good sized fish that can attain a length of almost 10 inches (25 cm) in the wild, though it is more common at about 6 – 8 inches (15 – 20 cm) in the aquarium. It’s colored with a bold pattern of white and black bands contrasted with bright yellow fins and it has a wonderful long extension to its dorsal fin. There are a number of rather descriptive common names including Longfin Bannerfish, Bannerfish, Pennant Coralfish, Wimple Fish, Featherfin Coralfish, Coachman, Threadback, and Reef Bannerfish.

This is a very popular butterflyfish and an excellent choice for the aquarists with some experience, especially for an aquarist who craves having a Moorish Idol Zanclus cornutus. These two species are quite similar in appearance but the Black and White Heniochus is hardier and much easier to care for. It is also less expensive and so often called the “Poor Man Moorish Idol”.

This fish is much better suited for the average aquarist with some fish keeping experience than the Moorish Idol is. It will readily accept all kinds of foods and has a much higher survival rate. Thus the reason we are tempted to call it the “Sane Man’s Moorish Idol”! The Moorish Idol on the other hand is very difficult to maintain, and should only be attempted by an expert. Your best bet for success with the heniochus butterflyfish is making sure you get a healthy specimen. These are one of those fish that comes to the dealer in either good shape or in bad shape. Choose a specimen that’s been at the fish store for two to three weeks and is eating, alert, and disease free., This will give you a great chance of success at keeping this fish.

It does need a good sized aquarium that is well established. A 55 gallon tank is the minimum size for a single fish and a bigger tank will be needed if you want to keep more than one. They need some rockwork, preferably well developed live rock that offers a cave or overhangs along with plenty of swimming space. This species is not suitable for reef tanks as they will eat coral polyps. They are best kept in a “fish only aquarium” (FO) or in a “fish only with live rock” aquarium (FOLR).

These are peaceful fish and suitable for a community tank with other peaceful inhabitants. They shouldn’t be kept with more aggressive fish. They like the company of their own kind as well, and will be more active, but they should be kept in odd numbers. When kept with their own kind they tend to form a type of social hierarchy in a captive setting. If they are kept in pairs one fish may dominate the other and cause problems.

Another butterflyfish that is easily confused with this species is its close relative the False Moorish Idol or Pennantfish Heniochus diphreutes. These two are almost identical and it’s very difficult to tell apart unless they are seen side by side. They do differ slightly in form. The Pennantfish has a slightly longer snout, rounder shape, and a longer and more angular anal fin. Though it can be variable, the best clue to help the hobbyist distinguish them is in the color on the tip of the anal fin. Follow the inside edge of the rear black band as it extends onto the anal fin. On the Black and White Heniochus it will arch slightly back towards the tail, leaving most of the tip of the anal fin white. On the Pennantfish the edge will tend to go straight down onto the anal fin (at a 90° angle with the tail), leaving more black. The Black and White Heniochus is the one most often found in the aquarium trade. The False Moorish Idol is only occasionally found, usually coming from Hawaii.

For more Information on keeping saltwater fish see:
Marine Aquarium Basics: Guide to a Healthy Saltwater Aquarium

Moorish Idols and Black and White Heniochus

Report Broken Video
Undersea video of a large school of Black and White Heniochus in their natural environment!

Wonderful video taken under the sea and featuring a huge number of Black and White Heniochus schooling in their natural environment.

  • Kingdom: Animalia
  • Phylum: Chordata
  • Class: Actinopterygii
  • Order: Perciformes
  • Family: Chaetodontidae
  • Genus: Heniochus
  • Species: acuminatus
Black and White Heniochus – Quick Aquarium Care
  • Aquarist Experience Level: Beginner
  • Aquarium Hardiness: Moderately hardy
  • Minimum Tank Size: 55 gal (208 L)
  • Size of fish – inches: 9.8 inches (24.99 cm)
  • Temperament: Peaceful
  • Temperature: 72.0 to 78.0° F (22.2 to 25.6&deg C)
  • Range ph: 8.1-8.4
  • Diet Type: Omnivore
Enter a Saltwater Aquarium
  • My Aquarium – Enter your aquarium to see if this fish is compatible!
Popular Searches

Habitat: Distribution / Background

The Black and White Heniochus Heniochus acuminatus was described by Linnaeus in 1758. They have a very wide distribution. They are found in the Indo-Pacific from East Africa and the Arabian (Persian) Gulf in the west to the Society Islands (French Polynesia) in the east with the exception of the Marquesas Islands, north to southern Japan and south to Lord Howe Island. They are also found throughout Micronesia.

This species is on the IUCN Red List as Least Concern (LC). They have a wide distribution and a global population. They are generally common and are found in many marine protected areas. Although they are harvested for the aquarium trade with possible declines in some localities, there are no major threats overall. Other common names they are known by include Longfin Bannerfish, Bannerfish, Pennant Coralfish, Wimple Fish, Featherfin Coralfish, Coachman, Threadback, Pennant Bannerfish, Pennant Coral Fish, and Reef Bannerfish.

These butterflyfish are associated with coral and rocky reefs. They are found in protected lagoons and channels and at the deeper parts of outer reef slopes. They inhabit depthsbetween 6 1/2 – 246 feet (2 – 75 meters), but are most commonly found below 33 feet (10 m). Adults, though sometimes seen alone, are often found in pairs. As juveniles they are solitary. They feed mostly on plankton but will also eat benthic invertebrates. Juveniles have been observed picking parasites from the skin of other fish. Being planktivorous they will generally stay within a few meters of a reef.

  • Scientific Name: Heniochus acuminatus
  • Social Grouping: Groups – Adults are often seen in pairs, though sometimes seen singly. Juveniles are solitary.
  • IUCN Red List: LC – Least Concern

Description

The Black and White Heniochus is very distinctly shaped and colored. The body is disc-like and it has a protruding snout tipped with a small mouth. It has an an elongated dorsal fin and a rounded tail fin. Adults can grow to 9.84″ (25 cm) in the wild, though are more common at about 6 – 8″ (15 – 20 cm) in the aquarium. They have a lifespan of about 5 years or more if properly maintained.

The adult H. acuminatus is white with two broad black vertical bands on its sides and another black mark extending down the front of its face creating a mask around its eyes and snout. The dorsal, pectoral and tail fins are a bright yellow.

  • Size of fish – inches: 9.8 inches (24.99 cm) – In the aquarium they usually only reach 6 – 8.5 inches.
  • Lifespan: 5 years – They can live 5 years or more if properly cared for.

Fish Keeping Difficulty

The Black and White Heniochus not a difficult fish to keep in an established captive environment as long as its needs are met. No technical care is needed to for its maintenance and so it can be suggested for a beginning aquarist. It will take a variety of foodsandwill become a fairly hardy pet. As it will harm polyps of some stony and soft coral species and it feeds a variety of small benthic invertebrates in the wild, it is not recommended for reef-type aquariums.

  • Aquarium Hardiness: Moderately hardy
  • Aquarist Experience Level: Beginner

Foods and Feeding

The Black and White Heniochus are omnivores. In the wild these fish are planktivores but will also eat benthic invertebrates. Young specimens have even been known to act as cleaner fish, eating parasites off of other fish. In the aquarium feed live brine, worms, a good angel or marine formula and a spirulina formula. Offer various foods quite frequently at first. Feed it at least twice a day, and if it is a tiny juvenile feeding should be tried three to four times everyday.

  • Diet Type: Omnivore – In the wild they are planktivores and will also eat benthic invertebrates.
  • Flake Food: Yes
  • Tablet / Pellet: Yes
  • Live foods (fishes, shrimps, worms): Some of Diet
  • Vegetable Food: Some of Diet
  • Meaty Food: Some of Diet
  • Feeding Frequency: Several feedings per day – Offer various foods quite frequently at first. Once acclimated adults need at least 2 feedings a day and juveniles need 3 to 4.

Aquarium Care

Once it is successfully acclimated it will become a durable, long lived fish. No special care or technique is needed to maintain this fish in the aquarium. Frequent water changes are not necessary, rather normal water changes at 10% biweekly or 20% monthly are fine. Sudden massive water changes can cause trouble

  • Water Changes: Bi-weekly – Change 10% biweekly or 20% monthly and avoid sudden massive water changes.

Aquarium Setup

This fish is known as a coral eater, nipping the polyps of some stony and soft coral species. Consequently it is not recommended for reef-type aquariums. They are best kept in a “fish only aquarium” (FO) or in a “fish only with live rock” aquarium (FOLR). It will need a good sized aquarium that is well established, matured for at least six or more months. They need a well lit aquarium with good water movement.

They do need a lot of space to swim as they can reach 8 inches or so in length. A 55 gallon tank is the minimum size for a single fish, and a bigger tank will be needed if you want to keep more than one. They need some rockwork, preferably well developed live rock, that offers a cave or overhangs along with plenty of swimming space.

  • Minimum Tank Size: 55 gal (208 L) – A single fish will require 55 gallons minimum.
  • Suitable for Nano Tank: No
  • Live Rock Requirement: Typical Plus Hiding Places
  • Substrate Type: Mix – Sand + Coral
  • Lighting Needs: Moderate – normal lighting – It is best kept under the normal lighting conditions, but can also be kept under very bright light as long as some dimly lit spaces are provided.
  • Temperature: 72.0 to 78.0° F (22.2 to 25.6&deg C) – This species lives in tropical areas. Temperatures between 72 – 78° F (22 – 25° C) will serve them well.
  • Specific gravity: 1.020-1.025 SG
  • Range ph: 8.1-8.4
  • Brackish: No
  • Water Movement: Moderate – A moderate water movement is fine. It can tolerate a rather strong flow but a moderate or slow-moving water will be more favorable
  • Water Region: All – It swims freely and usually spends time in the open water at all levels of the aquarium.

Social Behaviors

These are peaceful fish and suitable for a community tank with other peaceful inhabitants. This fish can be kept singly but also likes the company of its own kind and will be more active if kept in a small group. If keeping more then one they should be kept in odd numbers as they tend to form a type of social hierarchy. If they are kept in pairs one fish may dominate the other and cause problems.

Black and White Heniochus pair, Heniochus acuminatus
Photo © Animal-World

As this species is not an aggressive fish so it is best to select tank mates that are not overly territorial or aggressive. Smaller non-aggressive fishes like Chromis or other damsels make good companions. Also hardy cardinalfish, gobies, tilefish, fairy basslets, fairy and flasher wrasses are also good candidates as tank mates. Small but very territorial fishes like dottybacks should be avoided. Such fish as Basses or scorpionfish, even if they are small enough, should also be avoided.

  • Temperament: Peaceful
  • Compatible with:
    • Same species – conspecifics: Yes – They will be more active when kept with their own kind, but they should be kept in odd numbers. In pairs one will dominate the other.
    • Peaceful fish (gobies, dartfish, assessors, fairy wrasses): Safe
    • Semi-Aggressive (anthias, clownfish, dwarf angels): Safe
    • Monitor
    • Large Semi-Aggressive (tangs, large angels, large wrasses): Monitor
    • Large Aggressive, Predatory (lionfish, groupers, soapfish): Threat
    • Monitor
    • Anemones: Monitor
    • Mushroom Anemones – Corallimorphs: Monitor
    • LPS corals: Threat
    • SPS corals: Threat
    • Gorgonians, Sea Fans: Threat
    • Leather Corals: Threat
    • Soft Corals (xenias, tree corals): Threat
    • Star Polyps, Organ Pipe Coral: Threat
    • Zoanthids – Button Polyps, Sea Mats: Monitor
    • Sponges, Tunicates: Monitor
    • Shrimps, Crabs, Snails: Monitor
    • Starfish: Monitor
    • Feather Dusters, Bristle Worms, Flatworms: Monitor
    • Clams, Scallops, Oysters: Monitor
    • Copepods, Amphipods, Mini Brittle Stars: Threat

Sex: Sexual differences

No sexual difference is noted for this species. Butterflyfish species studied up to this time indicate that these fish are gonochoristic, meaning that each fish is either a male or a female and they do not change sex.

Breeding / Reproduction

This species has not been cultivated in captivity. In the wild butterflyfish are pelagic spawners that release many tiny eggs into the planktonic water column where they float with the currents until they hatch. Once hatched the fry are in a post-larval where their body, extending from the head, is covered with large bony plates.

Marine butterflyfish have not reportedly been spawned successfully in captivity. There are, however, reports of some success in rearing wild collected larvae of some of the corallivorous butterflyfish. It is hoped these captive reared fish will be adapted to accept aquarium foods, and thus broaden the species selections that can be sustained in captivity. For more information see, Marine Fish Breeding: Butterflyfish.

  • Ease of Breeding: Unknown

Fish Diseases

Black and White Heniochus are generally hardy and disease is not usually a problem in a well maintained aquarium. Any additions to a tank can introduce disease, so it’s advisable to properly clean or quarantine anything that you want add to an established tank prior to introduction.

Diseases that marine Butterflyfish are susceptible to include Marine Ich(white spot disease), Marine Velvet, Uronema marinum, and Lymphocystis. Sometimes they suffer from “ich” (white spot disease) and other infectious diseases. They are not overly sensitive to copper medications and can be treated successfully.

Bannerfish are also prone to “lateral-line disease” which can quickly lead to death. The best defense is to obtain a healthy specimen that has been at the dealers for at least a few days before purchase, and ideally 2 to 3 weeks. If it does exhibit signs, try using antibiotic-fortified flake foods, as gram-negative antibiotics have been found helpful. Furacyn medications may also help. For information about saltwater fish diseases and illnesses, see Aquarium Fish Diseases and Treatments.

Availability

This fish is generally readily available in pet stores and online, and is relatively moderate inprice.

References


 Heniochus acuminatus (Image Credit: Suzelfe, Wikimedia Commons CC BY-SA 4.0 International)