Brittle Sea Star Diet

Brittle stars belong to the class Ophiuroids, in the phylum Echinodermata. This means they're technically not starfish or sea stars, but close relatives. There's no such thing as a "brittle sea star" species. Thousands of brittle star species exist, employing various feeding methods.

  1. Scavengers

    • Most of the brittle stars that find their way into tropical fish tanks are scavengers. These brittle stars will sift their way through sand. They live off detritus and other organic matter other animals leave behind. Their diet can include the waste of other animals as well as bits of organic matter like dead animals and bits of algae.

    Predators

    • Despite their innocent appearance, some brittle stars are actually predators. Some predatory brittle stars eat tiny animals that live in substrate, and their habits are almost indistinguishable from scavenging brittle stars. But some brittle stars, like green brittle stars (Ophiarachna incrassata) will actually push their disks off the seafloor with their arms and wait for an animal to come by. Once they feel an animal crawl under them, these brittle stars drop down and catch it. Sometimes they catch fish this way.

    Suspension Feeders

    • The brittle star group includes highly specialized creatures called basket stars. They sit upside down relative to other brittle stars, with their mouths pointed upward. Their tangled, branching arms filter plankton and tiny crustaceans from the water column. Theirfeeding is called suspension feeding or filter feeding. Their tangled limbs form a bowl shape, giving them their common name.

    In the Aquarium

    • In a reef aquarium, you usually don't have to take care of brittle stars. This is because scavenging brittle stars wind up in reef aquariums more often than other species. They will survive just fine on other species' leftovers. If you have basket stars, you need to give them targeted feedings of tiny crustaceans like brine shrimp and copepods. Predatory brittle stars do not make good additions to most aquariums since they can manage to catch fish. Saltwater fish can be very expensive pets, especially if you have to keep replacing them.