Bicolor Parrotfish (Cetoscarus Bicolor)

Also Known As: Two-Color Parrotfish, Irobudai

Compatibility and Behavior The Bicolor Parrotfish (Cetoscarus bicolor) is one of the most charming juveniles in the marine hobby, and the juvenile coloration is what most aquarists fall in love with at first sight. The body shows a clean silvery white base set off by a bold orange mask across the face, with matching orange accents on the dorsal and anal fins. The look is genuinely unmistakable, and the small, chunky profile gives this fish a real personality even at sale size. Juveniles are typically peaceful and curious, spending much of their time exploring the rockwork and grazing on algae as they slowly start to develop the characteristic parrot-like beak that defines the family. As they mature, the coloration will eventually transition into the very different adult phase of vivid blue-green with pink or purple edging, though most aquarium specimens are kept and traded in the juvenile stage. Behavior-wise, juveniles get along well with most peaceful to moderately assertive tankmates and rarely cause trouble at this stage. The one important point is that Bicolor Parrotfish are not considered reef safe. Even small juveniles may pick at live stony corals, soft corals, and hard-shelled invertebrates as they graze, so this is really a fish for FOWLR setups rather than coral-focused displays.

Aquarium Requirements A juvenile Bicolor Parrotfish can be kept in a more modest setup than its adult requirements would suggest, but it's important to plan ahead. A FOWLR aquarium with plenty of mature live rock, dead coral skeletons, and natural surfaces for algal growth gives the fish the grazing environment it needs to develop properly. Long-term, this species can reach a substantial adult size, and a much larger system will be required as it grows. Many hobbyists either commit to upgrading down the road or trade the fish along once it outgrows their setup. Strong, stable filtration matters from day one, since these fish are constant grazers and produce significant waste relative to their size. Moderate to strong flow, good oxygenation, and a tight-fitting lid or canopy round out the setup. Even small juveniles can startle and jump when something unexpected happens. Offer frequent feedings of algae-based foods, nori, frozen mysis shrimp, finely chopped seafood, and quality herbivore preparations to keep grazing behavior natural and body condition strong as the fish grows.

Specifications
Approximate Size: Sm: 1-2", Md: 2-3", Lg: 3-4"
Diet: Omnivore (algae-based foods, nori, frozen mysis shrimp, chopped seafood, quality herbivore preparations)
Origin: Indo-Pacific 
Care Level: Intermediate 
Reef Safe: No (may graze on live corals and invertebrates; best suited to FOWLR aquariums)
Temperament: Generally peaceful toward most other fish; can be territorial toward other parrotfish or similarly shaped species in smaller tanks
Minimum Tank Size: 75 gallons
Special Considerations: Will grow fairly large over time; not suited to coral-focused reefs; tight-fitting lid recommended; high bioload requires robust filtration and maintenance