Indigo Hamlet (Hypoplectrus indigo)

The Indigo Hamlet is a rare Caribbean reef fish. Known for its rich sapphire to deep indigo-blue colouration and bold, inquisitive nature. Unlike many cave-dwelling reef fish that remain hidden, the Indigo Hamlet confidently patrols its territory, weaving through rockwork while carefully observing everything around it. Its monochromatic colour makes it stand out against vibrant corals, offering a unique contrast that few marine fish can match. Although peaceful with most reef inhabitants, this species has a naturally predatory instinct toward tiny crustaceans, making it best suited for reef aquariums with appropriately sized tankmates.

Suggested parameters

• Temperature: 24–26°C (75–79°F)

• Salinity: 1.025–1.026 SG

• pH: 8.1–8.4

• Alkalinity: 8–10 dKH

• Calcium: 400–450 ppm

• Magnesium: 1250–1400 ppm

• Nitrate: 2–20 ppm

• Phosphate: 0.03–0.10 ppm

Care and temperament

• Difficulty: Easy to Moderate

• Temperament: Semi-aggressive

• Reef safe: Yes, with corals; use caution with very small ornamental shrimp and tiny crustaceans

• Minimum tank size: 40 gallons (150 litres)

• Appreciates an aquascape with plenty of caves, ledges, and swim-throughs

• Establishes a territory but usually ignores unrelated fish that do not compete for the same space

• Best maintained as a single specimen unless housed in a very large aquarium

• Can become defensive toward other hamlets, basslets, or similarly shaped fish

• A secure lid is recommended, particularly during acclimation

Diet

The Indigo Hamlet is an opportunistic carnivore and eagerly accepts a varied diet.

• Frozen mysis shrimp

• Enriched frozen brine shrimp

• Chopped shrimp, clam, squid, and krill

• High-quality marine pellets

• Premium marine flakes

• Feed once or twice daily, rotating foods to promote long-term health and vibrant colouration

Compatibility and tankmates

• Excellent with tangs, clownfish, gobies, blennies, cardinalfish, anthias, fairy wrasses, and dwarf angelfish

• Completely safe with all corals

• Compatible with larger ornamental shrimp, snails, and crabs

• May consume tiny shrimp species or very small crustaceans

• Avoid large predatory fish such as groupers, lionfish, and triggerfish

• Should not be housed with other hamlets or territorial basslets in smaller aquariums

Health and acclimation notes

The Indigo Hamlet is generally a resilient species that settles into captivity with minimal difficulty when introduced to a mature aquarium. A slow drip acclimation of 45–60 minutes is recommended. New arrivals often spend their first day or two becoming familiar with the aquascape before confidently claiming a section of rockwork as their own. Offering frozen mysis shortly after introduction usually encourages an early feeding response and helps reduce stress.

What you are buying

You will receive: 1 Indigo Hamlet (Hypoplectrus indigo)

This species displays deep indigo to sapphire-blue colouration, with natural variation in shade depending on age, mood, lighting, and collection locality. Size and colour intensity will vary from fish to fish.

A mature aquarium with stable water quality and ample live rock is recommended. Slow drip acclimation is encouraged before introduction. The Indigo Hamlet is an uncommon and rewarding Caribbean species that offers colour and confident behaviour without posing a risk to corals.

Why we love it

• Rich sapphire-blue colouration unlike almost any other Caribbean reef fish

• Rarely available and highly sought after by collectors

• Confident, inquisitive behaviour makes it enjoyable to observe

• Easy to care for in a mature marine aquarium

• Safe with corals and most community reef fish

• A unique display fish that adds bold colour and character to any reef aquarium