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FishMarineIntermediate

Royal gramma

Gramma loreto

The Royal Gramma is a colorful Caribbean basslet featuring a striking purple and yellow body. Peaceful yet territorial, it requires a nano-reef with ample caves and a carnivorous diet of plankton.

Taxonomy

Class:Actinopteri

Order:Perciformes

Family:Grammatidae

Genus:Gramma

Species:Gramma loreto

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Water Temperature

24 - 28 °C

pH Value

8.1 - 8.4

Water type

Marine

Tank level

Bottom and middle

Adult size

8 cm

Minimum tank volume

>= 120 L

Minimum group

>= 1

Species description

Geographical Origin and Habitat: Native to the Caribbean Sea and the western tropical Atlantic Ocean. Inhabits coral overhangs, shady caves and reef slopes, often swimming upside down keeping its belly close to the rocky ceilings.

Taxonomy and Morphology: Royal Gramma. It is a Basslet (Grammatidae), not a dottyback. Fusiform and compact body, reaches 8 cm (3 inches). Prominent eyes and a small mouth armed with micro-teeth to catch plankton. Recognizable by the broken lateral line.

Social Behavior: Peaceful, shy but proud defender of its den (a crevice in the live rock). It will open its mouth wide in a threatening attitude to chase away intruders, without however coming to a physical clash. Multiple individuals fight fiercely in small tanks.

Coloration and Sexual Dimorphism: Unmistakable bicolor: the anterior half is brilliant fuchsia/purple, which fades abruptly into a bright golden yellow in the posterior half and tail. It has a black spot on the dorsal fin and a black line through the eye. Males slightly larger.

Care, breeding and tankmates

Aquarium Setup: Ideal for nano-reefs (minimum 100 liters / 25 gallons). The live rock must be architected to form countless caves, ravines and overhangs. Without adequate hiding places it wastes away from stress. Loves penumbra areas and moderate currents. Cover necessary (they jump).

Diet and Feeding: Planktivorous carnivore (darts from its den to grab morsels and returns). Very adaptable: accepts mysis, frozen brine shrimp, fish eggs, calanus and quickly gets used to high quality carnivore micro-pellets. Feed 1-2 times a day.

Water Quality: Robust, among the most recommended marine fish for beginners. Salinity 1.023-1.025, temperature 24-28°C (75-82°F). Good general tolerance to parameters, but the water must be mature to ensure the abundance of amphipod microfauna.

Compatibility and Cohabitation: Perfectly Reef Safe (ignores corals and ornamental shrimp). Gets along with Clownfish, Blennies and small Gobies. Do not pair it with the similar and much more aggressive Pseudochromis paccagnellae (Bicolor Dottyback), which would kill it.

Aquarium Breeding: Possible. The male builds a tiny nest in his cave weaving pieces of algae. After an elaborate courtship, the female lays filaments of adhesive eggs that the male will vigorously defend until hatching (5-7 days).

Risks and Diseases: Basically healthy, but can contract Ich (Cryptocaryon) if subjected to thermal shocks. Problems almost always stem from aggression by territorial dottybacks and damselfish or from the lack of adequate caves in which to retreat.

Geographic Origin and Distribution

Native to the Caribbean Sea and the western tropical Atlantic Ocean. Inhabits coral overhangs, shady caves and reef slopes, often swimming upside down keeping its belly close to the rocky ceilings.

Origin

Tropical oceans and reefsCentral America and CaribbeanNorth America

Fish profile

Temperament: Peaceful
Diet: Omnivore
Sex ratio: Group
Feeding frequency: Twice daily
Bioload: Medium
Flow: Strong
Jump risk: No
Reproduction: Oviparous
Compatibility & tankmates: Territorial
Tank level: Middle/Bottom

FishBase

Window to the official scientific data of the species

Data synced on: 06/15/2026

Scientific Parameters & Models

Trophic level: 3.3 ± 0.41 se
Phylogenetic uniqueness (PD50): 0.5313
Bayesian Length-Weight: a = 0.01122, b = 3.04

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.

Related species

Recommendations grouped by close relatives, companion choices, and similar care.

Variants and close relatives

Same atlas type, nearby scientific identity, genus, or family.

Blackcap Basslet

Gramma melacara

Species description

Care, breeding and tankmates