Common name: Chinaman rockcod

Scientific name: Epinephelus rivulatus (Valenciennes, 1830)

General information

The Blotchy Rockcod, also known as the Speckled Grouper or Maori Grouper, is a robust and striking species that can make a fascinating addition to larger marine aquariums. This species is known for its distinctive coloration, with a pattern of dark blotches and spots on a lighter background that can vary significantly among individuals.

In the wild, Epinephelus rivulatus is a predator, feeding on a variety of smaller fish and invertebrates. This predatory nature should be considered when choosing tank mates, as they may see smaller fish as prey.

Details

Recommended minimum volume
500 liter (130 gallons)
Salinity
S.G. 1.020 to 1.025
Temperature
22 to 28 °C (72 to 82 °F)
Acidity
pH 8.1 to 8.4
Average size
75 cm (2′6″)
Care level
Moderate to difficult Needs large tank, caves
Diet
Carnivore Prefers live or frozen food
Social
Solo Territorial, best kept alone
Reefsafe
No May eat smaller fish, inverts
Aggression
Semi aggresive Aggressive, especially to conspecifics
Captive bred
No
Conservation status
ExtinctThreatenedLeastConcern

Taxonomy

  1. Kingdom
    Animals
    Animalia
  2. Phylum
    Chordates
    Chordata
  3. Class
    Ray-finned Fishes
    Actinopterygii
  4. Order
    Perch-like Fishes
    Perciformes
  5. Family
    Groupers
    Serranidae
  6. Genus
    Grouper
    Epinephelus
  7. Species
    Chinaman rockcod
    Epinephelus rivulatus (Valenciennes, 1830)
  8. Synonyms
    Epinephelus grammatophorus Boulenger, 1903
    Epinephelus homosinensis Whitley, 1944
    Epinephelus matterni Fowler, 1918
    Epinephelus raymondi Ogilby, 1908
    Epinephelus rhyncholepis (Bleeker, 1853)
    Epinephelus spiramen Whitley, 1945
    Epinephelus viridipinnis De Vis, 1885
    Serranus rhyncholepis Bleeker, 1853
    Serranus rhyncolepis Bleeker, 1853
    Serranus rivulatus Valenciennes, 1830
    Serranus viridipinnis De Vis, 1884

Care

The Blotchy Rockcod requires a spacious aquarium due to its potential size, with plenty of rockwork and hiding places to mimic its natural habitat. They are generally hardy and adaptable to aquarium life but need a varied diet of meaty foods such as fish, squid, and crustaceans to maintain their health.

Due to their size and dietary needs, they produce a significant amount of waste, so efficient filtration and regular water changes are essential to maintain water quality.

Reproduction

In the wild, groupers like the Blotchy Rockcod are protogynous hermaphrodites, meaning they start life as females and can change to males as they mature. Breeding them in captivity is challenging due to their size and the complexity of their reproductive behavior.

Habitat

Epinephelus rivulatus is found in the Indo-Pacific region, from the Red Sea and East Africa to Samoa, north to southern Japan, and south to Australia. They prefer reef environments and are often found in lagoons and on outer reef slopes.