Pinkfish Sea Cucumber (Holothuria edulis) Care Guide
Holothuria edulis is an Indo-Pacific detritivorous sea cucumber that processes seabed sand, suited to mature reef aquariums.
Compiled by Aquairi from published sources · Published · Updated
Overview
Holothuria edulis is a medium-sized sea cucumber of the family Holothuriidae. According to Wikipedia, it typically has a dark reddish-black colour on its upper side and a pinkish-mauve colour below, though grey or dark brown individuals occur. It is a deposit feeder that ingests sediment and returns cleaned sand, making it a useful detritus processor in established reef systems.
Taxonomy
- Family: Holothuriidae
- Genus: Holothuria (subgenus Halodeima)
- Scientific name: Holothuria edulis
- Authority: Lesson, 1830 (WoRMS accepted)
Habitat
The species ranges across the Indo-Pacific, from the Red Sea and East African coast to Sri Lanka, Japan, China, Indonesia, the Philippines, northern Australia and various Pacific islands. It is found down to about 20 metres, inhabiting sandy or muddy substrates, coral rubble, seagrass meadows, reef flats and lagoons.
Tank requirements
- Minimum tank volume: 200 L
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Salinity: 1.024-1.026 SG
- dKH: 8-11
- Adult size: 15-30 cm; Wikipedia reports up to about 30 cm
- Lifespan: 5-10 years
Diet
Holothuria edulis is a detritivore. Per Wikipedia it feeds by ingesting sand and debris accumulated on the seabed, extracting organic matter and expelling the indigestible material. In aquariums it requires a mature deep sand bed with accumulated detritus to sustain it; it feeds continuously and is not target-fed.
Compatibility
This is a peaceful, reef-safe bottom dweller. Recommended tank mates are non-aggressive reef fish. Avoid keeping it with triggerfish or pufferfish, which may bite or harass it. As with other sea cucumbers, it may release a toxin when stressed, though Wikipedia notes this happens only very rarely in aquaria.
Breeding
The species has separate sexes and is a broadcast spawner that can spawn at any time of year, producing planktonic larvae. Wikipedia also notes asexual reproduction, where an individual can break into two parts that each regrow the missing organs. Captive breeding is considered impractical.
Conservation status
IUCN Red List: Least Concern, as reported by Wikipedia.
Holothuria edulis Breeding Guide
Overview
Holothuria edulis, the pinkfish sea cucumber, is an Indo-Pacific holothurian reaching about 30 cm in length, usually dark reddish-black above and pinkish-mauve below. It is a detritivore that ingests sand and accumulated debris from the seabed with its feeding tentacles, occurring on sandy and muddy substrates, coral rubble and seagrass meadows down to about 20 m.
Reproductive Mode
The species has separate sexes and reproduces both sexually and asexually. Sexually it is a broadcast spawner, liberating gametes into the water column where fertilisation occurs; it can spawn at any time of year.
Asexual Reproduction
Holothuria edulis can also reproduce asexually by transverse fission, breaking into two parts, each of which then regrows the missing organs. This contributes to local population increase independently of larval recruitment.
Sexual Reproduction
Following external fertilisation the larvae are planktonic. As in sea cucumbers generally, development passes through a ciliated auricularia and then a barrel-shaped doliolaria before the juvenile form is reached, requiring an extended planktonic feeding period.
Common Challenges
The planktonic auricularia stage cannot be sustained in a display aquarium, so sexual propagation is not achieved at home. The toxin this species may release when stressed, although it does so only rarely, is an additional risk when handling or if the animal dies in the tank.