Bimaculatus Anthias - Female

Female Bimaculatus Anthias, Pseudanthias bimaculatus, bring a brilliant combination of pink and yellow coloration to the marine aquarium. Females display a vivid pink body accented by yellow coloration through the dorsal, anal, and caudal fins, giving them a bright yet refined appearance as they swim actively through the water column. Their color, movement, and natural schooling behavior make them especially attractive additions to larger reef aquariums and fish-only marine aquariums.

Native to the Indo-West Pacific, including East Africa, the Maldives, and Indonesia, this species inhabits reef-associated coastal drop-offs and spends much of its time feeding on small planktonic prey in open water. In the aquarium, females are particularly well suited to harem-style groups and are generally less territorial than mature males, although a social hierarchy will still develop.

Like other anthias, Bimaculatus Anthias are protogynous hermaphrodites. In a group without a dominant male, a dominant female may transition into a male, making group composition an important consideration when planning a long-term display.

Quick Care Guide

Care Level: Moderate
Minimum Tank Size: 125 gallons
Temperament: Semi-aggressive
Diet: Carnivore / Planktivore
Reef Safe: Yes
Region: Indo-West Pacific – East Africa, Maldives, and Indonesia
Scientific Name: Pseudanthias bimaculatus

Tank Requirements

A mature, stable aquarium with excellent water quality is strongly recommended. Provide substantial open swimming space through the middle and upper portions of the aquarium along with well-developed rockwork containing caves, overhangs, and crevices where the fish can retreat when resting or feeling threatened.

Good water movement and strong oxygenation help replicate the conditions associated with their natural reef habitat. Because anthias are active swimmers and frequent feeders, efficient filtration is important for maintaining consistently high water quality.

A secure lid or mesh aquarium cover is recommended, as anthias can jump when startled or during periods of acclimation. With an adult size approaching approximately 5 inches, this species should be given ample swimming space for long-term housing.

Diet and Feeding

Bimaculatus Anthias are primarily planktivorous carnivores that naturally feed on small zooplankton and crustaceans carried through the water column. Captive specimens should receive a varied diet of small, nutrient-rich marine foods.

Offer enriched mysis shrimp, enriched brine shrimp, copepods, frozen plankton, finely chopped marine seafood, quality frozen carnivore blends, and appropriately sized marine pellets. Foods suspended or moving through the water column often stimulate the strongest feeding response.

Feed small portions at least two to three times per day. More frequent small feedings can be especially beneficial for maintaining proper body condition and supporting their naturally active feeding behavior.

Temperament and Tankmates

Females are generally more social and less territorial than mature males, making them well suited to group or harem-style displays. A group may consist of several females with one established male, provided the aquarium offers sufficient swimming room and hiding areas.

Some chasing and dominance behavior can occur as the group establishes its hierarchy. If no male is present, the dominant female may eventually transition into a male.

Suitable tankmates include clownfish, gobies, blennies, fairy and flasher wrasses, tangs, and other non-predatory marine fish. Avoid excessively aggressive tankmates that may prevent anthias from feeding comfortably or force them to remain hidden.

Reef Compatibility

Bimaculatus Anthias are considered reef safe. They do not normally damage or consume corals, clams, or other sessile reef organisms and are generally compatible with ornamental shrimp, crabs, and snails.

As natural planktivores, they will consume copepods and other tiny planktonic organisms present in the aquarium, but this feeding behavior is normal and does not typically present a concern in an established reef system.

Water Parameters

Temperature: 74–78°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Stable water quality is more important than continually adjusting the aquarium to achieve an exact number. Avoid rapid changes in temperature, salinity, or other major parameters.

Common Considerations

• Frequent small feedings are important because of the species' natural planktivorous feeding behavior.

• Females can be maintained in groups or as part of a harem with a single male in an appropriately sized aquarium.

• A dominant female may transition into a male when an established male is absent.

• Provide a secure lid because anthias can jump when startled.

• Mature rockwork, strong oxygenation, open swimming space, and stable water quality are important for successful long-term care.