Porcelain Anemone Crab

*Anemone not included.

Porcelain Anemone Crabs are very unique crustaceans that can make an interesting addition to reef aquariums housing a wide range of anemone species. These crabs have a commensal relationship with their anemone hosts, similarly to clownfish. In exchange for the anemone’s protection, the crabs offer the anemone cleaning and another source of food through their messy consumption of prey. Unlike many other commonly kept crabs, Porcelain Anemone Crabs are primarily filter feeders and can often be seen waving their large, feathery setae around to capture particulate food out of the water column, making up the majority of their diet. These crabs will also scavenge for any pieces of meaty foods when given the opportunity. Porcelain Anemone Crabs are reef safe and pose no danger to corals.

Quick Care Guide

Care Level: Easy
Minimum Tank Size: 10 gallons (larger if keeping a host anemone)
Temperament: Peaceful
Diet: Filter Feeder
Reef Safe: Yes
Adult Size: About 1 inch across the body
Region: Indo-Pacific
Scientific Name: Neopetrolisthes maculatus

Host Anemones

In the wild, the Porcelain Anemone Crab lives among the tentacles of large host anemones, most often carpet anemones (Stichodactyla), along with Heteractis species and sometimes bubble tip anemones. In the aquarium, a healthy host anemone is strongly recommended for long-term success. Some crabs will settle into rockwork crevices without one, but they are less secure and more exposed to predators.

If a clownfish already occupies the anemone, the fish may chase the crab out of it. Most crabs simply relocate to the anemone’s base or nearby rock.

Tank Requirements

An established reef aquarium with moderate, consistent water movement suits this porcelain crab best. Flow should carry suspended food past it without constantly knocking it off its perch. Rockwork with small holes and ledges gives it secure places to retreat during molts.

Diet and Feeding

Porcelain crabs catch food with fan-shaped mouthparts that sweep the water column. In a very clean aquarium, they can slowly starve without deliberate feeding.

Offer fine foods such as live or frozen phytoplankton, rotifers, copepods, oyster eggs, and powdered reef foods several times per week. Turning off return pumps and skimmers for a few minutes during feeding, and gently releasing food upstream of the crab with a baster, helps ensure it eats.

Temperament and Tankmates

Porcelain Anemone Crabs are peaceful toward fish, corals, and other invertebrates. They may squabble with another porcelain crab that crowds their spot, so keep one per anemone unless you have a pair.

Avoid hawkfish, triggerfish, puffers, and large wrasses, all of which may eat small crabs.

Reef Compatibility

This crab is reef safe. It does not pick at corals or clams, and its filter feeding helps remove fine particles from the water.

Water Parameters

Temperature: 75–80°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Acclimate gradually and keep salinity and temperature stable, as sudden swings can trigger failed molts. Invertebrates are highly sensitive to copper, and copper-treated water or medications should never be added to an aquarium that houses them.

Common Considerations

• Anemone not included: The crab is sold on its own. Have an established host anemone in place for the best results.

• Feed fine foods: Filter feeders need regular small-particle feedings, not just leftovers.

• Claws can drop: Stressed crabs sometimes release a claw. It regrows over successive molts.

• Molts look like a dead crab: Check for a hollow shell before assuming the crab has died.