Candy Cucumbers (Colochirus Crassus)

Candy Cucumber — Colochirus crassus

Candy Cucumber is a small, colorful filter-feeding sea cucumber from the Indo-Pacific. Its bright yellow body and branching feeding tentacles make it one of the most unusual invertebrates for a mature reef aquarium.

Unlike sand-sifting sea cucumbers, Colochirus crassus feeds directly from the water column. Once it finds a suitable location with steady flow, it often remains in the same area and extends its branching tentacles to capture fine suspended food particles.

Care Level: Moderate
Reef Safe: Yes
Temperament: Peaceful
Maximum Size: approximately 3–4 in
Temperature: 75–81°F
Salinity: 1.024–1.026
Lighting: Low to Moderate
Water Flow: Moderate to Strong
Diet: Filter Feeder
Origin: Indo-Pacific

For long-term success, Candy Cucumbers should be kept in an established reef aquarium with regular availability of fine suspended foods. Feed phytoplankton, zooplankton, rotifers, microplankton, and other fine particulate foods several times per week or in small daily feedings. A well-fed specimen will regularly extend its feeding tentacles into the current.

Avoid aggressive fish and protect all pump and wavemaker intakes. Like other sea cucumbers, severe injury or extreme stress may potentially release defensive compounds into the aquarium, although this is considered uncommon in healthy, properly maintained specimens.

Important: This species is sensitive to copper-based medications and sudden changes in water parameters.

Why we like it:
Candy Cucumbers are compact, brightly colored, peaceful, and fascinating to watch while feeding. Once settled into good flow, they often remain in one location and repeatedly extend their colorful feeding crown to collect plankton from the water column.