Bennett's feather star (Oxycomanthus bennetti) care guide

Group
Other invertebrates
Other names
Anneissia bennetti, Feather star, Comanthus bennetti, Cenolia bennetti, Actinometra bennetti
Family
Comatulidae
Origin
Indo-Pacific from the Bay of Bengal and the Maldives to the Marshall Islands, China and northern Australia; 5–25 m
Water
saltwater
Maximum size
30 cm
Care level
expert
Temperament
peaceful
Reef safe
yes
Flow
Strong, variable current carrying plenty of food

Care

Bennett's feather star is one of the larger feather stars (crinoids), reaching about 30 cm across, with 31–120 feathery arms. Colours range from yellow and brown to purple, and the pinnule tips are often brighter. Its accepted name is now Anneissia bennetti; Oxycomanthus bennetti is the older name still used in some sources. Unlike many feather stars it is active by day. In the wild it sits on exposed coral heads in currents, most often at 5–25 m, and holds its arms up to catch passing food. Young animals are anchored on a stalk; adults break free and cling on with their cirri (long gripping legs), and can crawl or swim. Feeding guide: feather stars are filter feeders and are very hard to keep fed; most imported animals slowly starve within weeks or months. Only consider one for a large, mature, plankton-rich system with strong, variable flow, where you can dose fine phytoplankton and zooplankton foods several times a day without harming water quality. They are delicate to handle and should never be lifted out of the water, as the arms break off. They are best left in the sea unless you have experience and a dedicated system. Copper: copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most other invertebrates. Never dose them in a tank holding this animal, and check the label of any treatment or fertiliser before use. Sources: Wikipedia (en.wikipedia.org/wiki/Oxycomanthusbennetti). Checked October 2026.

Diet

Filter feeder taking detritus, phytoplankton and zooplankton from the current. In captivity it needs frequent feeding with fine plankton foods (live or bottled phytoplankton, rotifers, copepods, oyster eggs), spread through the day. Most starve in normal reef tanks.

Breeding

Separate sexes. Gametes are released when pinnules burst; fertilised eggs hatch into free-swimming larvae that settle after a few days, grow a stalk and later break free. Not bred in aquaria.

Compatibility and tank mates

Reef safe and harmless, but easily damaged. Do not keep with fish or invertebrates that pick at it: angelfish, butterflyfish, triggers, puffers, many wrasses and large crabs. Powerheads and overflows can trap and tear the arms. It often carries harmless commensal worms.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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