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Chocolate tang (Yellow mimic tang)

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Acanthurus pyroferus (Mimic Tang / Chocolate Tang)

Small fish safe: ✅ Yes

Small invert safe: ✅ Yes

Coral safe: ✅ Yes

Minimum tank size: 400L+

Adult size: ~25 cm

Diet: Herbivorous (marine algae, seaweed, spirulina-based flakes/pellets, occasional meaty foods)

Be aware of: Changes appearance as it matures—juveniles mimic dwarf angelfish species. Can be territorial toward other tangs, especially in smaller tanks. Needs a high-fiber diet to stay healthy.

Mimic Tang (Acanthurus pyroferus) – A Master of Disguise and Excellent Algae Grazer

The Mimic Tang, also known as the Chocolate Tang, is a unique and fascinating member of the Acanthuridae family. Unlike other tangs, juvenile Mimic Tangs mimic dwarf angelfish species, such as the Lemonpeel Angelfish (Centropyge flavissima), Eibl’s Angelfish (Centropyge eibli), or Half Black Angelfish (Centropyge vrolikii). This mimicry helps them avoid predation in the wild. As they grow, they lose their angelfish-like appearance and develop a more traditional tang shape and coloration.

Appearance and Coloration

The Mimic Tang’s appearance changes significantly from juvenile to adult:

Juveniles closely resemble dwarf angelfish species, often exhibiting bright yellow, orange, or brownish tones, depending on the region they originate from.

Adults develop a more uniform brown, tan, or olive coloration with subtle dark markings near the face and a darker tail.

• The transformation typically begins when the fish reaches 8-12 cm in length and completes by adulthood.

This colour shift makes them one of the most visually dynamic tang species in marine aquariums.

Natural Habitat and Behaviour

Mimic Tangs are found in tropical reefs across the Indo-Pacific, typically in lagoon areas and reef slopes at depths of 2 to 25 metres. In the wild, they:

Live among reefs and rocky structures, grazing on algae throughout the day.

Swim actively, requiring plenty of space.

Form loose groups or swim independently, unlike some shoaling tang species.

In an aquarium, they are constant grazers, relatively peaceful, and highly active, making them a great addition to reef tanks.

Tank Requirements and Water Parameters

While not as large as some other tangs, the Mimic Tang still requires a moderate to large tank due to its active swimming nature.

Minimum tank size: 400L+ (larger preferred for long-term care)

Temperature: 23–26°C

pH: 8.1–8.4

Salinity: 1.020–1.025

Water movement: Moderate to strong, mimicking reef conditions

Filtration: High-capacity filtration and protein skimming recommended

Live rock with plenty of algae growth is highly beneficial for their grazing behaviour.

Diet and Feeding

Mimic Tangs are primarily herbivorous, feeding on macroalgae and detritus in the wild. To stay healthy, they require a high-fiber diet rich in marine vegetation.

Recommended foods include:

Dried seaweed (Nori) – Essential for digestion and overall health

Spirulina-based flakes and pellets – Helps maintain coloration and immunity

Fresh macroalgae – Such as chaetomorpha or gracilaria

Occasional meaty foods – Enriched brine shrimp or mysis shrimp (as a supplement only)

They should be fed multiple times per day to support their natural grazing habits and prevent stress-related illnesses. A lack of algae in their diet can lead to deficiencies such as HLLE (Head and Lateral Line Erosion).

Compatibility and Tank Mates

Mimic Tangs are generally peaceful, making them a good choice for community reef tanks. However, they can become territorial toward other tangs, especially if space is limited.

Best tank mates include:

✔ Clownfish

✔ Wrasses (Fairy Wrasses, Halichoeres species)

✔ Gobies and blennies

✔ Angelfish (both dwarf and large species)

✔ Other peaceful to semi-aggressive reef-safe fish

Avoid housing with:

❌ Other Acanthurus tangs unless in a very large system

❌ Very aggressive tang species (e.g., Sohal Tang, Clown Tang)

❌ Slow-moving or timid fish that may struggle to compete for food

If housing multiple tangs, introduce them simultaneously in a large tank to reduce aggression.

Health and Disease Considerations

Mimic Tangs are hardy, but like all tangs, they can be prone to certain health issues:

Marine ich (Cryptocaryon irritans) – A common issue if they are stressed or exposed to poor water conditions. Quarantining new additions is strongly recommended.

Head and Lateral Line Erosion (HLLE) – Can occur if they are not provided with enough marine algae or exposed to poor water quality.

Nutritional deficiencies – If not fed a balanced, algae-rich diet, they may develop digestive issues and faded coloration.

To keep them healthy:

Ensure a varied, algae-rich diet with plenty of seaweed.

Maintain stable water conditions to reduce stress.

Quarantine new fish to prevent disease outbreaks.

Lifespan and Long-Term Care

With proper care, Mimic Tangs can live up to 10-12 years in captivity. Their peaceful nature, algae-grazing behaviour, and fascinating colour transformation make them an excellent choice for reef tanks.

Why Choose a Mimic Tang?

Unique colour-changing species – Juveniles mimic angelfish before transitioning into adult coloration.

Great for algae control – Constant grazer, helps keep the tank clean.

Generally peaceful – Suitable for mixed-reef communities.

Hardy and adaptable – Easier to keep than some other Acanthurus tangs.