Bartlett's Anthias - Male

Male Bartlett’s Anthias is a brilliantly colored saltwater fish distinguished by intense violet, magenta, and lavender tones accented by a vivid yellow upper body and tail. Mature males develop stronger coloration and more pronounced fin extensions than females, giving them a particularly striking appearance under reef aquarium lighting. Their constant midwater activity adds both movement and color to established marine displays.

Nemanthias bartlettorum, also widely known in the aquarium trade by the former scientific name Pseudanthias bartlettorum, naturally inhabits Pacific coral reefs where groups typically contain relatively few males alongside numerous females and juveniles. These active marine aquarium fish occupy the water column above reef structure, feeding primarily on passing zooplankton.

A male Bartlett’s Anthias can make an impressive centerpiece for a reef aquarium or peaceful fish-only aquarium. It may be maintained singly or as the dominant male in a carefully planned group of females, provided the aquarium offers sufficient swimming space, retreat areas, stable water quality, and frequent feeding.

Quick Care Guide

Care Level: Moderate
Minimum Tank Size: 70 gallons
Temperament: Semi-aggressive
Diet: Planktivore / Carnivore
Reef Safe: Yes
Region: Central and Western Pacific
Scientific Name: Nemanthias bartlettorum

Tank Requirements

Provide a mature saltwater aquarium with substantial rockwork along with generous open swimming space. Caves, ledges, overhangs, and crevices allow the fish to retreat when resting or threatened, while unobstructed midwater areas accommodate its active swimming and feeding behavior.

Moderate to strong, varied water movement is ideal and reflects the current-swept reef habitats where Bartlett’s Anthias naturally occur. Efficient filtration, good oxygenation, and consistently high water quality are especially important because the species benefits from frequent feeding.

A secure lid or mesh cover is strongly recommended. Anthias can jump when startled, during acclimation, or while being chased by tankmates. When maintaining a male with females, provide sufficient rockwork and visual breaks so subordinate fish can move away from the dominant male when necessary.

Diet and Feeding

Bartlett’s Anthias naturally feeds on zooplankton and should receive a varied selection of small, protein-rich marine foods. Excellent choices include frozen mysis shrimp, enriched brine shrimp, copepods, finely chopped marine seafood, frozen plankton blends, and appropriately sized high-quality marine pellets or flakes.

Several smaller feedings throughout the day are preferable to a single large meal whenever practical. Newly introduced specimens may initially respond more readily to frozen or live foods before accepting dry prepared diets consistently.

A mature aquarium containing copepods and other microcrustaceans can provide useful supplemental feeding opportunities, but naturally occurring foods should not replace regular feeding.

Temperament and Tankmates

Male Bartlett’s Anthias are generally compatible with peaceful to moderately assertive marine fish but can become territorial toward other anthias, particularly other males or individuals beginning to develop male characteristics.

A male may be kept singly or with several females in a suitably sized aquarium. In group settings, one established male with multiple females is generally the preferred arrangement. Avoid maintaining multiple mature males together unless the aquarium is exceptionally large and provides ample separation, as competition and persistent aggression may occur.

Suitable tankmates include many peaceful reef community species that will not intimidate the anthias or prevent it from feeding. Highly aggressive or predatory fish are less appropriate.

Reef Compatibility

Bartlett’s Anthias is considered reef safe and is well suited to coral-dominated aquariums. It does not normally consume or damage stony corals, soft corals, anemones, or clams.

Its feeding behavior is directed primarily toward planktonic organisms in the water column. Established ornamental shrimp, crabs, snails, and other common reef invertebrates are generally compatible.

Water Parameters

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

Stable conditions are more important than continually adjusting the aquarium to reach an exact number within these ranges. Maintain excellent filtration, strong oxygenation, and consistent water quality.

Common Considerations

• Male aggression: An established male may chase females and can be territorial toward other male or transitioning anthias.

• Group structure: When keeping a group, one male with several females generally provides the most natural social arrangement.

• Frequent feeding: Several smaller meals throughout the day help support this active planktivore.

• Jumping risk: A secure aquarium lid or mesh cover is strongly recommended, particularly during acclimation or periods of social aggression.

• Open swimming space: Although rockwork is important for security, ample midwater swimming room is essential for normal long-term behavior.