This month I’ll discuss an animal that many unsuspecting marine aquarists purchase for use as scavengers or “clean up” help for their fish only or reef aquariums and
then within a few months of their purchase mysteriously start losing their piscine pals (fish) one by one, likely having no idea where they’re going! If you’ve not yet
had this experience, let this article be your warning to NOT purchase the highly predatory Ophiarachnid brittle stars! (Please note the Ophiarachnids herein referenced
should not be confused with Ophiocoma, the black, brown, or red brittles with a smaller central disk, which are peaceful detrital feeders that will not harm their tankmates.)
An Ophiarachnid is a star that when young and small will serve as a great scavenger. However, with time and increased size and appetite, this star becomes a skilled
predator! It has five long, spiny arms coming off the central disk. Once it snags its prey with its long arms, it feeds it up into the opening in the underbelly of the oral disk,
which can open quite large to accommodate its feeding habits. This star can reach well over a foot when mature, and with it comes a big appetite! They’re nocturnal by
nature and “night-time is the right time” for them to feed and your fish to disappear! The star will “perch” on its arms and become perfectly still, which makes for an
alluring hiding place for an unsuspecting fish. The fish swims in under the arms thinking he’s in a safe place, and wham! – the Ophiarachnid snatches it up with its arms
and transfers it up into its underbelly! Also, reference is made by Anthony Calfo and Bob Fenner in their extraordinary book, “Reef Invertebrates, An Essential Guide to Selection,
Care, and Compatibility,” about this star not only eating fish but also being known for attacking shrimp and bivalves, including Tridacna clams! Buyer beware! If you are
considering this echinoderm for addition to your tank, think again! This applies to any animal you may be considering for addition to your fish only or reef aquarium.
Do your homework! Research the species you are interested in BEFORE you make your purchase. You should also verify information you get from your local fish
stores and/or online retailers or anyone from whom you may make a purchase. If you have a local fish store you trust and where you know you can count on being
provided reliable and accurate information, you will be in a position to make an informed decision about your purchases and prevent expensive losses to predators
about which you were not informed or had no knowledge.
In conclusion, the Ophiarachnids are beautiful and intelligent animals, but if you are inclined to keep one or more, we recommend you do so in a separate system
where you can actually hand-feed them and admire their beauty and behavior without them presenting a deadly threat to certain of their tankmates! Unfortunately,
although this echinoderm is long-lived and incredibly hardy, we cannot give it a blue thumbs up for the community marine system!
(Please remember the Ophiarachnids herein referenced should not be confused with Ophiocoma, the black, brown, or red brittles with a smaller central disk, which are
peaceful detrital feeders that will not harm their tankmates.)
That’s it for this month. Thanks for visiting our website and reading our article. We hope you enjoyed it. Keep reefing, and we’ll see you at All-Reef!