Amphiprion clarkii (Clarkii Clownfish / Yellowtail Clownfish)
• Small fish safe: ✅ Yes
• Small invert safe: ✅ Yes
• Coral safe: ✅ Yes
• Minimum tank size: 100L+ (preferably 150L+ for pairs or anemone hosting)
• Adult size: ~15 cm (6 inches)
• Diet: Omnivorous (marine pellets, flakes, frozen mysis/brine shrimp, and algae-based foods)
• Be aware of: One of the most aggressive clownfish species. Will become highly territorial, especially if hosting an anemone. Best kept singly or in a bonded pair.
Clarkii Clownfish (Amphiprion clarkii) – A Hardy and Bold Anemonefish
The Clarkii Clownfish, also known as the Yellowtail Clownfish, is one of the most adaptable and hardy clownfish species in the marine aquarium trade. It is known for its striking coloration, aggressive personality, and ability to host a wide variety of anemones. While larger and more dominant than many other clownfish, it is a great choice for aquarists looking for an active and resilient fish.
Appearance and Coloration
Clarkii Clownfish exhibit a range of colors, but their most common features include:
• A deep orange or brownish body that may darken with age.
• Three distinct white bands—one behind the eye, one in the middle of the body, and one near the tail.
• Bright yellow or orange fins and tail, giving them a unique contrast.
• Females grow larger and darker than males, as clownfish are protandrous hermaphrodites (all start as males and can become females when needed).
Juveniles tend to be brighter and more vibrant, with more pronounced white bands.
Natural Habitat and Behaviour
Clarkii Clownfish are found throughout the Indo-Pacific region, including the Red Sea, Indian Ocean, and Western Pacific. In the wild, they:
• Live in symbiosis with anemones, often defending their host aggressively.
• Form strong pair bonds, with a dominant female leading a small social structure.
• Are one of the least picky clownfish species when it comes to anemone hosting, often seen inhabiting various species.
In captivity, they do not require an anemone, but they will still attempt to host corals, rock formations, or artificial decorations.
Tank Requirements and Water Parameters
Clarkii Clownfish are tough and adaptable, but they still need a well-maintained environment with stable parameters.
• Minimum tank size: 100L+ (150L+ recommended for pairs or anemone hosting)
• Temperature: 24–27°C (75–81°F)
• pH: 8.1–8.4
• Salinity: 1.020–1.025
• Water movement: Moderate (not too strong, as clownfish are not powerful swimmers)
• Filtration: Good-quality filtration and regular water changes to maintain stable water parameters
If hosting an anemone, ensure high lighting and stable water conditions to support its health.
Diet and Feeding
Clarkii Clownfish are omnivores, requiring a varied diet for optimal health and coloration.
Recommended foods include:
• High-quality marine pellets and flakes – Provides balanced nutrition.
• Frozen mysis and brine shrimp – Excellent protein sources.
• Chopped seafood (shrimp, squid, or fish) – Occasional treats.
• Algae-based foods or spirulina – Supports digestion and enhances coloration.
They should be fed 1-2 times per day, in small portions to prevent overfeeding.
Compatibility and Tank Mates
Clarkii Clownfish are one of the most aggressive clownfish species, especially when hosting an anemone. They will defend their space fiercely, which makes careful tank mate selection essential.
Best tank mates include:
✔ Semi-aggressive tank mates such as dwarf angelfish (Flame Angelfish, Coral Beauty), wrasses, and tangs.
✔ Hardy, fast-moving fish that can hold their own (such as damselfish, basslets, or larger gobies).
✔ Invertebrates such as shrimp, snails, and crabs are generally safe.
Avoid housing with:
❌ Other clownfish species, unless in an extremely large tank to prevent aggression.
❌ Small, timid fish (e.g., Firefish, small gobies) that may be bullied.
❌ Very aggressive species that may stress or outcompete them for food.
Clarkii Clownfish should be kept singly or in a bonded pair, as multiple individuals will fight for dominance in smaller tanks.
Hosting Anemones
Clarkii Clownfish are one of the least selective species when it comes to hosting anemones. They will often inhabit:
• Bubble Tip Anemone (Entacmaea quadricolor)
• Sebae Anemone (Heteractis crispa)
• Long Tentacle Anemone (Macrodactyla doreensis)
• Carpet Anemone (Stichodactyla gigantea)
⚠ Important Notes:
• Anemones require strong lighting (LEDs, metal halides, or T5s) and stable water conditions.
• They are not required for clownfish to thrive.
• Anemones should only be kept by experienced aquarists.
Health and Disease Considerations
Clarkii Clownfish are very hardy, but they can be prone to some common saltwater fish diseases:
• Marine Ich (Cryptocaryon irritans) – Often triggered by stress or poor water quality. Quarantining new fish is recommended.
• Brooklynella (Clownfish Disease) – A parasite common in clownfish. Symptoms include excessive mucus production and difficulty breathing.
• Bacterial Infections (Fin Rot, Open Sores) – Often caused by poor water quality or stress.
To keep them healthy:
✔ Provide a stable environment with good water quality.
✔ Offer a varied diet rich in vitamins and marine algae.
✔ Quarantine new fish before introducing them to the main tank.
Lifespan and Long-Term Care
With proper care, Clarkii Clownfish can live up to 10-15 years in captivity. Their long lifespan, bold personality, and striking coloration make them a great choice for aquarists who enjoy more active and dominant fish.
Why Choose a Clarkii Clownfish?
✔ Bright yellow and orange coloration with three distinct white bands.
✔ Extremely hardy and adaptable, making them a good choice for beginners and advanced aquarists alike.
✔ Can live long lives, up to 15 years in captivity.
✔ Will host a wide variety of anemones (if provided).
✔ Active, entertaining, and full of personality.
⚠ Important Considerations Before Buying a Clarkii Clownfish:
🚫 One of the most aggressive clownfish species – Best kept singly or in a bonded pair.
🚫 Defensive of their territory – Will chase away intruders, especially if hosting an anemone.
🚫 Requires a moderate to large tank – Needs space to swim and establish its territory.