Brittle star (Ophiocoma spp.) care guide

Group
Other invertebrates
Other names
Ophiocoma brittle star, Spiny brittle star, Black brittle star, Ophiocoma echinata, Ophiocoma wendtii, Ophiocoma scolopendrina
Family
Ophiocomidae
Origin
Tropical reefs; Ophiocoma echinata and O. wendtii are common in the Caribbean, other species in the Indo-Pacific
Water
saltwater
Maximum size
25 cm
Temperature
22–26°C
pH
8.1–8.4
Hardness
dKH 8–12, SG 1.023–1.025
Care level
intermediate
Temperament
semi_aggressive
Reef safe
yes

Care

Ophiocoma is a genus of large, spiny brittle stars in the family Ophiocomidae. Species include O. aethiops, O. echinata, O. erinaceus, O. scolopendrina and O. wendtii. Brittle stars have a small round central disc and five long, flexible, spiny arms that they move like snakes; Ophiocoma are among the larger ones, up to about 25 cm across the arms. LiveAquaria sells its Caribbean 'brittle sea star' as Ophiocoma echinata (and lists it under Ophiotrichidae, although Ophiocoma belongs to Ophiocomidae). They are nocturnal, hiding under rock by day with an arm or two showing and coming out at night to scavenge. In the aquarium they make good scavengers for a mature reef or fish-only tank with plenty of rock to hide under, eating detritus, leftover food and small organisms. Keep one per tank unless it is large. They are very sensitive to sudden changes in oxygen, salinity and pH, so drip-acclimatise slowly and never lift them into air. Small brittle stars that appear on their own with live rock (mini brittle stars, usually Amphipholis or Ophiactis) are harmless, helpful hitchhikers. Large Ophiocoma are generally safe too, but well-fed big ones can catch small fish or shrimp at night. Copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most invertebrates. Sources: LiveAquaria (liveaquaria.com/products/brittle-sea-star); Wikipedia (en.wikipedia.org/wiki/Ophiocoma). Checked October 2026.

Diet

An omnivorous scavenger: eats detritus, leftover food and small organisms, mostly at night. Feed a varied diet of frozen mysis, brine shrimp and finely chopped prawn and mussel, placed near its arm tips or under its rock a few times a week.

Breeding

Sexes are separate. Brittle stars spawn into the water and some species can also reproduce by splitting; Ophiocoma are not normally bred in aquaria. They can regrow lost arms.

Compatibility and tank mates

Reef compatible: does not harm corals. Large individuals are semi-aggressive and may catch small, sleeping fish, small shrimp or crabs, so avoid very small tankmates. Harlequin shrimp, triggers, puffers and some wrasses may attack it. Do not confuse with the green brittle star (Ophiarachna incrassata), a known fish-eater.

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

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