Sand-Sifting Starfish Care Guide
Astropecten polyacanthus is a burrowing Indo-Pacific sea star that sifts sandy substrate for detritus and small invertebrates in marine aquariums.
Overview
The sand-sifting starfish (Astropecten polyacanthus) is a burrowing sea star of the family Astropectinidae, widespread across the Indo-Pacific. It spends much of its time buried in soft sediment and is mostly nocturnal, emerging to move through the substrate. The species sifts sand for food and is used in marine aquariums as a sand-bed cleaner.
Taxonomy
- Family: Astropectinidae
- Genus: Astropecten
- Scientific name: Astropecten polycanthus
- Accepted name (WoRMS): Astropecten polyacanthus Müller & Troschel, 1842
Habitat
It ranges throughout the Indo-Pacific, from the Red Sea and Zanzibar to Hawaii, and from Japan to Australia and New Zealand. The animal is often found on silty sand bottoms in harbours and estuaries and has been recorded to depths of about 185 metres. It burrows using pointed tube feet that lack suckers and are adapted for digging.
Tank requirements
- Minimum tank volume: 200 L
- Temperature: 24-27 °C (75-81 °F)
- pH: 8.1-8.4
- Specific gravity: 1.024-1.026
- Carbonate hardness (dKH): 8-12
- Water flow: low
- Arm spread: up to 20 cm
- Lifespan: 3-7 years
Diet
Astropecten polyacanthus is a detritivore that consumes detritus, leftover food and small organisms within the sand bed. In the wild it also takes bivalve and gastropod molluscs, swallowing them whole, and may ingest pebbles to digest biofilm on their surfaces. In aquariums its efficiency means it can deplete beneficial sand-bed microfauna in smaller tanks, so a deep, well-established sand bed is recommended.
Reef compatibility
The species is peaceful, bottom-dwelling and does not harm corals, so it is generally considered reef-compatible. It should be kept away from animals that prey on echinoderms, such as pufferfish, triggerfish and harlequin shrimp. A mature system with abundant sand-bed life is needed to sustain it long term.