By Bob Goemans
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Ocean Nutrition 


Chaetodon plebeius

Cuvier, 1831

Bluespot Butterflyfish, Bluebloch Butterflyfish

Not Reef Tank Suitable

Likely Fish-Only Tank Suitable

Range: Indo-West Pacific Ocean: Andaman Sea to Fiji, north to Southern Japan, and south to the Great Barrier Reef, Lord Howe Island and New Caledonia.

Size: 6 inches (15 cm)

Natural Environment: Inhabits shallow coral rich lagoons, reef slopes and reef faces at depths between 3 to 50 feet (1 – 15 m) and feeds mainly on stony coral polyps, i.e., Acropora and Pocillopora, along with minor amounts of filamentous algae.

General Husbandry: Quite attractive as it has a brilliant yellow body with a large elongated blue patch on its upper middle sides, a black spot edged in bluish white at the caudal peduncle, a black eye band also edged in bluish white, with the dorsal, anal, pelvic and tail fins bright yellow. Juveniles lack the blue patch on the sides of the body.

Best maintained in larger peaceful fish-only aquariums, especially those with lots of open swimming space, live rock hiding places, and having some micro and macroalgae growths. As to diet, a meaty diet of live fortified brine shrimp and/or black worms (Lumbriculus variegatus) is a good beginning. Once feeding regularly, various frozen meaty foods such as mysis, can be offered several times daily.

Even though basically a live coral polyp consumer in the wild, there’s evidence it also injests some algae in the wild, therefore, flake foods, especially those containing Spirulina and/or Nori should also be occasionally offered.

This is usually a difficult species to get feeding in the home aquarium, unless offered live stony coral polyps. If refusing to eat regular aquarium foods, try small human consumption clams/black mussels purchased in local grocery stores and placed on the half-shell in the aquarium, which may help entice it to begin feeding. Over time, frozen foods like mysis and brine shrimp and various flake foods may be more readily accepted.

Can be maintained with other butterflyfish species or this species, but all should be introduced at the same time.


    Order: Perciformes

    Suborder: Percoidei

    Family: Chaetodontidae

    Genus: Chaetodon

FYI: Pressing some soft foods into openings/crevices on a piece of old dead coral skeleton can sometimes encourage finicky eaters to begin feeding.

Experience Level: Intermediate/Professional

Temperament: Peaceful

Diet: Corallivore/Carnivore

Coral Safe: No

Invertebrate Safe: With caution

Acclimation Time: 30 minutes+

Aquarium Environment: Fish-only aquarium

Tankmates: Peaceful or non-aggressive

Minimum Tank Size: 75 gallons

Temperature Range: 72 - 82°F (22 – 28°C)

Specific Gravity: 1.020 -1.026

pH: 8.0 - 8.5

 Chaetodon plebeius (Bluespot Butterflyfish, Bluebloch Butterflyfish)
Photo © John Randall
 Chaetodon plebeius (Bluespot Butterflyfish, Bluebloch Butterflyfish)
Photo © Richard Field
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Polyp Lab