Black Tang (Zebrasoma Rostratum)

Also Known As: Black Longnose Tang

Compatibility and Behavior
The Black Tang (Zebrasoma rostratum) is one of the most sought-after tangs in the hobby, prized for its rarity and its dramatic, minimalist presence in a high-end reef. Robust, domineering, and confident, we call these the "military tanks" of the fish hobby. The body is a deep, velvety charcoal to jet-black, often picking up a subtle greenish sheen under strong reef lighting, and it's accented by a slender, elongated snout and delicate, translucent fins outlined in soft gray. The tall, sail-like dorsal fin and disc-shaped body give it the classic Zebrasoma profile, but the all-black coloration makes it read like a sleek shadow gliding through the rockwork. On temperament, Black Tangs tend to be peaceful to semi-aggressive and behave much like other Zebrasoma such as Yellow or Purple Tangs. They reserve most of their attitude for other tangs or similarly shaped algae grazers, especially in smaller or crowded systems, while generally coexisting well with a wide variety of community fish like clownfish, fairy wrasses, Anthias, and chromis. They're typically considered reef safe, spending much of the day browsing film and filamentous algae off rock and hard surfaces rather than picking at corals or ornamental inverts, though an underfed or stressed individual may occasionally nip. With careful stocking, room to roam, and steady access to algae-rich foods, they usually settle in as an active but manageable showpiece.

Aquarium Requirements
Black Tangs do best in mature systems with long horizontal swimming space and plenty of established live rock to graze. A tank at least 300 gallons with a long, open footprint is the right target for typical specimens in the trade, and additional volume is always a plus for long-term comfort and compatibility. Aquascape with open cruising lanes and a stable rock structure that creates arches, ledges, and shaded retreats where the fish can wedge itself at night or when startled. Strong, well-oxygenated flow and robust filtration help support their active lifestyle and maintain the clean, stable water they prefer. Frequent offerings of nori, marine algae, and varied herbivore foods will help them hold their body weight, curb aggression, and keep that dark, velvety coloration looking rich under reef lighting.

Specifications
Approximate Size: Lg: 5–6", XL: 6–7", XXL: 7–10"
Diet: Omnivore; Marine algae, nori, and spirulina-based foods, with occasional frozen mysis shrimp
Origin: Central Pacific
Care Level: Expert
Reef Safe: Generally reef safe; focuses on algae and biofilm rather than corals
Temperament: Peaceful to semi-aggressive; may be territorial toward other Zebrasoma and similar grazers
Minimum Tank Size: 300 gallons, with additional volume always beneficial given the larger sizes offered
Special Considerations: A rare, high-value tang best kept in a mature, very stable system