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Cleanup Crew

Choose the right workers for the job: algae grazers, leftover-food scavengers and sand-surface feeders have different needs.

Useful: a practical addition when properly fed. Caution: specialist care or compatibility risks. Start small and add only what your reef can sustain; cleanup animals recycle waste rather than exporting nutrients. Maintain filtration and routine cleaning.

Adult sizes are approximate: snail sizes describe shells, crab sizes state the measurement used, and star sizes include arms. Confirm the supplier’s species, acclimate to matched conditions and quarantine appropriately; do not use coral dips on cleanup animals.

Written by Christian, Signature FragsLast reviewed: 13 October 2026

Sand & specialist

All cleanup crew

Wedge sea hare

Caution

Dolabella auricularia

Specialist algae grazer; plan its long-term food supply.

Quick ID: Soft mottled body with short head tentacles and a distinctive flattened rear.
Typical adult size: Can reach around 20–30 cm overall; juveniles are much smaller.
Useful work: Consumes substantial filamentous algae where the species and algae are compatible.
Feeding & care: Guard all intakes and arrange ongoing algae food or responsible rehoming; never buy solely as a disposable treatment.
Best fit: Spacious, algae-rich established reefs with protected equipment.

Watch out for: Can starve after algae clears; vulnerable to pumps and may release ink if stressed. Not a universal Bryopsis or cyanobacteria solution.

Research sources

Species care and feeding reference

Black sand-sifting cucumber

Caution

Holothuria atra

Experienced-care deposit feeder; requires a large, mature sand resource.

Quick ID: Black elongated body, often partly dusted with sand; collects sediment with feeding tentacles.
Typical adult size: Commonly 20–30 cm; can grow larger.
Useful work: Ingests surface sediment and extracts associated organic food before passing cleaner sand.
Feeding & care: Provide extensive fine sand, protect pumps and avoid predators; handle gently and monitor feeding.
Best fit: Larger mature sand-bed reefs; not a default beginner purchase.

Watch out for: Can starve in immature tanks. Injury or severe stress can release harmful compounds; species identification is essential.

Research sources

LiveAquaria — Holothuria atra care and suitability

Published case report — apparent holothurin toxicosis in a home aquarium

Banded serpent star

Useful

Ophiolepis superba

A sheltered scavenger needing real food.

Quick ID: Small central disc with five long, clearly banded flexible arms.
Typical adult size: About 20–25 cm across fully extended arms; disc is much smaller.
Useful work: Reaches into crevices for food particles and meaty leftovers, especially after dark.
Feeding & care: Offer small meaty marine foods near its shelter and maintain stable salinity; never lift by an arm.
Best fit: Established reefs with caves and room for arm spread.

Watch out for: Large green brittle stars are different animals and may catch fish. Do not buy an unidentified “brittle star” as an equivalent.

Research sources

Species care and feeding reference

Sand-sifting starfish

Caution

Archaster typicus reference; Astropecten spp. also traded

Specialist sand feeder; usually a poor choice for small or young reefs.

Quick ID: Pale patterned five-armed star that spends much of its time in or on sand; several species share the retail label.
Typical adult size: About 10–15 cm arm span for common traded forms; species vary.
Useful work: Works surface sediment while feeding on organic material and, in some species, small sand-bed animals.
Feeding & care: Confirm species, require a broad mature sand bed and verify a sustainable food supply before purchase.
Best fit: Specialist established systems; a conch or modest snail crew is often easier to sustain.