Decorator Crab

Decorator Crab
Camposcia retusa or Cyclocoeloma tuberculata (varies)

The Decorator Crab is a fascinating and cryptic addition to a marine tank. It uses bits of algae, coral, and sponge to “decorate” its shell as camouflage. These crabs are true oddballs — slow-moving, nocturnal, and full of personality.

Quick Stats:

• Care Level: Easy

• Temperament: Peaceful (but opportunistic)

• Color Form: Brown to tan, often covered in living or synthetic material

• Diet: Omnivore – eats detritus, soft algae, meaty foods

• Reef Compatible: ⚠️ Caution – may nip soft corals or steal zoas for decoration

• Water Conditions:

  • Specific Gravity: 1.023–1.025

  • Temperature: 72–78°F

  • dKH: 8–12

  • pH: 8.1–8.4

• Max. Size: 3–5 inches

• Minimum Tank Size: 30 gallons

Why We Like Them:

• Camouflages with bits of coral, sponge, or algae

• Entertaining to watch and great for display tanks

• Helps clean up leftover food and detritus

• Nocturnal habits mean surprise appearances

🪸 Pro Tip:
While generally peaceful, they may grab polyps, zoas, or softies to “decorate” with. Avoid placing them in tanks with prized small corals or delicate frags.