Chocolate chip starfish (Protoreaster nodosus) care guide

Group
Other invertebrates
Other names
Horned starfish, Chocolate chip sea star, Horned sea star
Family
Oreasteridae
Origin
Western Pacific and Indo-Pacific, from Thailand to Samoa and Japan to New Caledonia; shallow sand, seagrass and mangroves
Water
saltwater
Maximum size
30 cm
Temperature
24–27°C
pH
8.1–8.4
Hardness
SG 1.023–1.026
Care level
intermediate
Reef safe
no

Care

The chocolate chip starfish is a stiff, heavy-bodied sea star, usually red, brown or tan, with rows of black cone-shaped knobs on top that look like chocolate chips. It normally has five tapering arms (four or six occur) and grows to about 30 cm across. Its tube feet are purple or pinkish. Small shrimps, brittle stars and young filefish often ride on it. Habitat: sheltered sandy or slightly muddy bottoms, seagrass meadows and mangroves rather than coral reefs, in shallow water. Set-up: a large, mature fish-only or rock-and-sand tank with plenty of open sand. The water figures are typical reef-tank guidance rather than from a source. It does not tolerate rapid changes: drip-acclimatise slowly over an hour or more, keep salinity stable and avoid lifting it into the air where possible. Reef safety: not reef safe. It is an opportunistic carnivore that eats hard and soft corals, sponges, clams and snails, and will climb onto corals to digest them. Conservation: heavy collection for the dried curio trade has hit wild populations. 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 read the label of any treatment, fertiliser or algae remover before use. Sources: Wikipedia (en.wikipedia.org/wiki/Protoreasternodosus). Checked October 2026.

Diet

An opportunistic carnivore: corals, sponges, snails and other sessile animals, and occasionally urchins. Feed pieces of mussel, clam, prawn, squid or fish placed under the star two or three times a week, plus sinking meaty pellets.

Breeding

Sexes are separate and it spawns by releasing eggs and sperm into the water; aggregations may help fertilisation. The larvae are planktonic. Not bred in home aquariums.

Compatibility and tank mates

Not reef safe: eats corals, sponges, clams, snails and sessile invertebrates. Generally ignored by fish, but harlequin shrimp eat it, and puffers, triggers and some angelfish may nip its tube feet. Fine with robust fish in a fish-only tank.

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

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