Care
Sand-sifting Starfish are widely distributed throughout much of the Indo-Pacific region, from the Red Sea and Zanzibar eastwards to Hawaii, and from Japan southwards to Australia and New Zealand. Here, they inhabit estuaries and harbours with silty substrates and shallow sandy coral reef areas. They remain buried in the substrate during the daytime and emerge at night to feed on bivalves, gastropods, and other small invertebrates that are living in the sand. Whilst the Sand-sifting Starfish has often been touted as a utility species, within the average sized aquarium, it will quickly eat its way through all the tiny invertebrates living in the sand bed - and is then likely to starve due to refusal to take other foods. This species is really only suitable for extremely voluminous systems with large open expanses of sand where the micro fauna in the deep sand bed is capable of reproducing at a rate that can cope with the starfish's ongoing search for small prey. Ensure that all rockwork is placed on the tank bottom rather than on top of the substrate, so it cannot be undermined by the burrowing behaviour of the starfish. Providing that a large enough, mature system can be offered, these critters make very good tankmates for most reef-friendly fish, corals, and other invertebrates, and should not pose a threat to their safety. However, avoid keeping alongside hermit crabs, which may inflict damage. Sand-sifting Starfish are extremely sensitive to changes in water chemistry and should be acclimatised very carefully and slowly over the course of a few hours via drip acclimatisation, in order not to shock them with any differences in salinity or pH. As these starfish are largely nocturnal, they will spend most of the day well-hidden, but will venture out to scavenge for food items at night. Many aquarists like to run a dim moon light during the evening in order to view their starfish as they go about their business under the subdued illumination.
Feeding
Feeds exclusively on micro fauna living within a mature, live sand bed.
Breeding
Most commonly reproduces asexually, when one arm pulls itself away from the central disc and walks away; the disc heals and grows a replacement arm, and the detached arm grows another body plus 4 additional arms. Can also reproduce sexually via gonochoric means, with the tiny embryos hatching into planktonic larvae, then later metamorphosing into pentamorous juveniles which develop into young starfish with stubby arms. Spawning of these starfish in the home aquarium is rare.
