Purple Tang (Zebrasoma xanthurum)
• Small fish safe: ✅ Yes
• Small invert safe: ✅ Yes
• Coral safe: ✅ Yes
• Minimum tank size: 400 liters (100 gallons)
• Adult size: Up to 25 cm (10 inches)
• Diet: Herbivorous, primarily feeding on algae
• Be aware of: Can be aggressive towards other tangs and similar-looking fish; requires ample swimming space; may establish dominance in smaller tanks
Appearance and Coloration
The Purple Tang is one of the most strikingly beautiful surgeonfish, featuring a deep royal purple body with a vivid yellow tail. Its body is covered in fine horizontal lines and tiny blue spots, creating a textured appearance. The contrast between the dark body and bright yellow tail makes it an eye-catching centerpiece in any marine aquarium.
Natural Habitat and Behaviour
Zebrasoma xanthurum is native to the Red Sea and Arabian Peninsula, where it inhabits coral reefs and rocky outcrops. It is commonly found at depths of 2 to 20 meters (7 to 65 feet), actively grazing on filamentous algae throughout the day.
In captivity, Purple Tangs are known for their bold and active personalities. They are constantly on the move, patrolling the tank and grazing on algae-covered surfaces. However, they can be territorial, especially towards other tangs and fish with similar body shapes.
Tank Requirements and Water Parameters
• Minimum Tank Size: 100 gallons (400 liters) for a single adult specimen
• Water Parameters:
• Temperature: 24°C – 28°C (75°F – 82°F)
• pH: 8.1 – 8.4
• Specific Gravity: 1.020 – 1.025
• Aquascaping:
• Plenty of open swimming space with rock structures for hiding.
• Ensure strong water flow to mimic natural reef conditions.
• Live rock with natural algae growth will encourage grazing behavior.
• Lighting: Moderate to bright, supporting algae growth.
• Water Movement: Strong and variable flow, simulating natural reef currents.
Diet and Feeding
Purple Tangs are herbivores that primarily graze on algae and seaweed in the wild. In captivity, they require a plant-based diet supplemented with occasional meaty foods.
• Natural Diet: Filamentous algae, macroalgae, and detritus.
• Captive Diet:
• Nori (dried seaweed)—secured with a veggie clip.
• Spirulina-based flakes and pellets.
• Blanched vegetables like spinach or zucchini.
• Occasional meaty foods (e.g., mysis shrimp, brine shrimp) for additional protein.
• Live rock with natural algae growth provides continuous grazing opportunities.
Feed at least 2-3 times per day to support its high metabolism and prevent aggression.
Compatibility and Social Structure
• Temperament:
• Can be aggressive toward other tangs, especially those of the Zebrasoma genus (e.g., Yellow Tang, Sailfin Tang).
• Less aggressive toward unrelated species, particularly peaceful community fish.
• May chase new tank mates until dominance is established.
• Tank Mates:
• Compatible with clownfish, wrasses, gobies, blennies, and larger angelfish.
• Avoid housing with other Purple Tangs or similar-shaped tangs unless in a very large system (200+ gallons).
• Reef Compatibility: 100% reef-safe—does not bother corals or invertebrates.
Important Considerations
• Aggression: Introduce last in a community tank to minimize territorial disputes.
• Algae Growth: Live rock with natural algae provides grazing opportunities and reduces aggression.
• Tank Size: Smaller tanks (below 100 gallons) will increase aggression and stress levels.
• Quarantine: Always quarantine new tangs to prevent disease introduction, especially Marine Ich (Cryptocaryon irritans), to which they are prone.