Black Cap Basslet

The Black Cap Basslet is a striking saltwater fish with an intense violet-to-magenta body and a contrasting blue-black cap extending across the head and upper back. Subtle blue accents around the eyes and fins become especially vivid under reef aquarium lighting, giving this compact marine aquarium fish a dramatic appearance without requiring the space of a large centerpiece species.

Native to the tropical western Atlantic, Gramma melacara occurs throughout the Greater Caribbean, including the Bahamas, West Indies, and parts of Central America. It naturally inhabits steep reef faces, vertical drop-offs, caves, and deep outer-reef ledges, where it often rests beneath overhangs or swims upside down beside rock surfaces. The species reaches approximately 4 inches and quickly retreats into crevices when threatened. 

Its brilliant coloration, manageable adult size, and dependable coral compatibility make the Black Cap Basslet highly desirable for established reef aquariums and peaceful fish-only aquariums. It is generally hardy once acclimated, although it may defend its chosen cave from other basslets and similarly shaped fish.

Quick Care Guide

Care Level: Easy to Moderate
Minimum Tank Size: 40 gallons
Temperament: Semi-aggressive
Diet: Carnivore / Planktivore
Reef Safe: Yes
Region: Greater Caribbean, including the Bahamas, West Indies, and Central America
Scientific Name: Gramma melacara

Tank Requirements

Provide a mature aquarium with substantial live rock arranged into caves, shaded overhangs, vertical surfaces, and narrow crevices. The Black Cap Basslet will typically select one protected retreat and spend much of its time hovering near the entrance. It may orient sideways or upside down beneath rock ledges, which is normal behavior rather than a sign of illness. 

Leave some open water around the rockwork for feeding and short swimming movements. Moderate, well-distributed flow is appropriate, but the aquascape should include calmer sheltered areas. A specialized substrate is not required, and either reef sand or fine gravel may be used.

Because this species naturally occurs on deeper reef faces, newly introduced specimens often appreciate subdued lighting and shaded retreats. It can adapt to normal reef lighting when adequate caves are available. Use a securely fitted lid or mesh cover, as basslets may jump when startled or chased. 

Diet and Feeding

The Black Cap Basslet is a carnivorous planktivore that feeds on zooplankton and small crustaceans around reef structures. In captivity, offer mysis shrimp, enriched brine shrimp, copepods, finely chopped shrimp or clam, small krill, frozen marine carnivore blends, and appropriately sized sinking or slow-sinking pellets. 

Feed one or two small meals daily, allowing food to drift near the fish’s preferred cave. Newly introduced individuals may be reluctant to move far into open water, so targeted feeding near the rockwork can help them settle in. A varied diet supports healthy body condition and strong coloration.

Temperament and Tankmates

The Black Cap Basslet is generally peaceful toward unrelated community fish but can become territorial once it establishes a cave. Suitable tankmates include clownfish, cardinalfish, gobies, blennies, firefish, peaceful wrasses, dwarf angelfish, and other non-predatory marine fish.

Keep one specimen in most home aquariums. Avoid combining it with other Gramma species, similarly shaped basslets, or assertive dottybacks unless the aquarium is considerably larger and provides clearly separated territories. A known compatible pair may be maintained in a spacious system, but two randomly selected individuals may fight.

Although confident around its shelter, this basslet may be intimidated by highly aggressive fish or exceptionally competitive feeders. Introduce it before more territorial species whenever possible.

Reef Compatibility

The Black Cap Basslet is considered reef safe. It does not normally damage stony corals, soft corals, zoanthids, anemones, clams, snails, or other sessile reef inhabitants. It is an excellent choice for coral-focused displays where vivid fish coloration is desired. 

Very small crustaceans, including copepods, amphipods, and tiny shrimp, may be consumed as natural prey. Healthy adult ornamental shrimp are generally left alone, but newly hatched or exceptionally small crustaceans should not be considered completely protected.

Water Parameters

Temperature: 75–80°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Maintain consistent salinity, good oxygenation, and stable water quality. Stability is more important than repeatedly adjusting the aquarium to reach a single exact value.

Common Considerations

• Provide shaded caves: Secure overhangs and crevices help this deeper-water basslet acclimate and display natural behavior.

• Use a secure cover: Basslets can jump when startled, pursued, or newly introduced.

• Expect territorial behavior: The fish may chase other basslets or similarly shaped species away from its chosen cave.

• Upside-down swimming is normal: It frequently orients itself to the ceilings and walls of caves and reef ledges.

• Allow time to settle: A new specimen may remain hidden and feed close to shelter before becoming more visible.