Harlequin Shrimp

With large purple-blue spots on its cream body, leaf-like flat antennae and huge paddle-shaped claws, the harlequin shrimp is one of the most unusual-looking shrimp. In the wild it feeds only on sea stars: it flips the star over and eats it over several days, starting with the tube feet. Providing this food regularly in the aquarium is difficult and costly; for this reason it is suitable only for experienced hobbyists. Although a limited number of captive-bred individuals are available, most in the trade come from the wild.

• 40 liters or more for a pair, a mature aquarium with plenty of caves.
• Salinity 1.023–1.026 specific gravity, pH 8.1–8.4, temperature 24–27°C.
• Reef-safe as far as corals are concerned, but it kills every sea star in the aquarium.
• It should be acclimated by the drip method for at least 1 hour; copper-based medications are lethal.

It eats only sea stars. A pair consumes a small star or one star arm every 1–2 weeks; hobbyists usually use pieces cut from chocolate chip starfish, which can regrow their arms, or Asterina stars that multiply in the aquarium. If the food supply stops, it dies quickly.

Calm and slow; pairs hunt together and share the same cave. It leaves fish and corals alone.

Good companions: small gobies, blennies, clownfish, cardinalfish; snails.

Avoid: all sea stars, such as sand sifting starfish, Fromia and Linckia; hawkfish, wrasses, triggerfish and pufferfish.