Saltwater Fish
Cooper's Anthias

Species Description…

Scientific Name: Pseudanthias cooperi (male)
Common Name: Cooper's Anthias
Species Group: Anthias
Habitat: Reef Safe
Care Level: Intermediate
Temperament: Semi-aggressive
Diet Type: Carnivore
Role in Aquarium: Schooling Fish
Max Fish Length: 6 (inches)
Min Aquarium Size: 125 (gallons)
Native Range: Indo-Pacific, from East Africa to Fiji, including the Great Barrier Reef
Pseudanthias cooperi (male) - Cooper's Anthias

Pseudanthias cooperi (male) (Cooper's Anthias)

Overview

  • Found throughout the Indo-Pacific region, particularly near coral slopes and reef drop-offs.
  • Males display a bold reddish-pink body with a lavender hue, while females are more orange or yellow-toned.
  • A mid-water schooling fish known for its beauty and peaceful nature.
  • Well-suited to intermediate aquarists who can provide appropriate tank size and feeding regimen.

Feeding

  • Planktivore; naturally feeds on zooplankton and suspended particulate matter.
  • Provide a diet rich in small, meaty foods such as mysis shrimp, enriched brine shrimp, and microplankton.
  • Feed 2–3 times per day to maintain energy levels and coloration.
  • Supplement with high-quality marine flake or pellet foods formulated for carnivores.

Habitat

  • Requires a tank of at least 70 gallons, with open space for swimming and live rock for shelter.
  • Stable, oxygen-rich water with moderate current is ideal.
  • Rockwork should provide both shaded retreat areas and vantage points for resting.
  • Ensure high water quality with regular maintenance and filtration.

Fish Care

  • Temperature: 72–78°F (22–26°C).
  • pH: 8.1–8.4; Specific Gravity: 1.020–1.025.
  • Very sensitive to fluctuating parameters; maintain consistency through routine care.
  • Monitor for signs of stress, particularly during acclimation and when kept in undersized groups.

Compatibility

  • Peaceful and best kept in a social structure of one male with several females.
  • Reef-safe and compatible with corals and most ornamental invertebrates.
  • Pair well with other peaceful community fish like firefish, wrasses, tangs, and gobies.
  • Avoid overly aggressive or fast-feeding tank mates that may outcompete for food.

Aquarium Behavior

  • Schooling fish that thrives in groups and prefers mid-water swimming zones.
  • Can be shy when first introduced; confidence builds with time and social presence.
  • Displays bold coloration and active behavior when kept in optimal conditions.
  • Regular, scheduled feeding helps promote visible activity and social interaction.