Blue Eye Tang (Ctenochaetus Binotatus)

Also Known As: Two-Spot Bristletooth Tang, Blueeye Kole Tang

Compatibility and Behavior
The Blue Eye Tang (Ctenochaetus binotatus) is a smaller bristletooth species that earns its keep, bringing constant, purposeful motion to the reef without the heavy bioload of bigger Tang species. The body runs a warm brown with fine darker spotting and a soft iridescent sheen, marked by two faint dark spots near the base of the dorsal fin and that namesake blue ring around the eye that really lights up under reef lighting. Temperament-wise, Blue Eye Tangs tend to be peaceful to semi-aggressive and are often milder than many of the larger Acanthurus tangs, particularly when given room and good rockwork. They're typically reef safe, spending the day picking film algae and detritus off rock, sand, and glass, so they pull double duty as a cleanup crew rather than bothering corals or ornamental inverts. They may spar with other tangs, especially other Ctenochaetus or similarly shaped grazers, but in most cases they coexist well with community fish like clownfish, wrasses, Anthias, gobies, and other smaller reef-safe species in a thoughtfully stocked tank.

Aquarium Requirements
Blue Eye Tangs do best in mature reef aquariums with plenty of live rock and a steady supply of biofilm and algae to graze. For small to medium specimens in the 1.5 to 3 inch range, a tank around 75 to 90 gallons is a solid starting point, with larger volumes preferred for long-term comfort and especially if you're housing other tangs. Aquascape with open swimming lanes and porous rock that offers ledges, caves, and shaded retreats while maximizing surface area for algae and film growth. Moderate to strong, well-oxygenated flow and solid filtration will support their active nature and grazing habits, and a secure lid or mesh top is recommended, since tangs can dash quickly when startled and may jump. Supplement their natural grazing with regular feedings of nori, spirulina-based foods, and quality herbivore fare to keep them well nourished, curb aggression, and maintain that subtle body patterning and bright blue eye ring.

Specifications
Approximate Size: Sm/Md: 1.5–3", Lg: 3–4"
Diet: Primarily herbivorous detritivore. Film algae, diatoms, detritus, nori, spirulina-based foods
Origin: Indo-Pacific reef regions
Care Level: Intermediate
Reef Safe: Yes
Temperament: Peaceful to semi-aggressive; may be territorial toward other bristletooth and similarly shaped tangs
Minimum Tank Size: Smaller specimens (Sm/Md) can start around 75 gallons, with larger volumes preferred long-term and if kept alongside other tangs
Special Considerations: A lighter-bioload, smaller tang species that doubles as a film-algae and detritus grazer