[mc_19]

i need help! i have a 40 gallon saltwater tank and i have a blue starfish! i really dont know the name of it but its blue and pretty nice but simple at the same time! what does it eat?

[leebca]

I moved this post to the Reef Aquariums Forum in hopes it will get attention.

[greenbean36191]

The name is probably Linckia. Nobody knows what they eat, but they seem to need a lot of established LR with lots of open surface area to graze on whatever it is that they're eating. Generally they don't take to supplemental feeding, so they don't last more than about 18 months in tanks with less than about 150 lbs of LR.

[Ninong]

Hi mc 19,



There is not much that I can add to what greenbean36191 has posted except to agree with him and point out that the blue sea stars that are commonly available in the hobby are usually Linckia laevigata.

This is not a good choice for a 40-gal aquarium for a couple of reasons: the animal gets too large and a 40-gal tank doesn't offer enough live rock and other substrata for grazing opportunities.

As far as sea stars go, this isn't a bad choice for an aquarium but it just requires a larger tank to survive for any reasonable length of time. That's assuming it wasn't damaged in collection and transport or during the final acclimation process. The chances of it successfully negotiating all of the various stages in the process from the time it is collected until the time you acclimate it to your tank are really quite slim and it could take weeks before the damage becomes obvious. If the animal was not properly acclimated to different water (e.g., salinity) conditions at any step of the way, the damage done is almost always fatal eventually.

While it is not known exactly what these sea stars eat in the wild, they have been observed grazing on algal films, microcrustaceans and organic/bacterial films in aquaria. Or, as one German source puts it, they are "scum suckers." The larger the aquarium, the more live rock and the better the chances are that the animal may find enough to eat. This species does not appear to be predatory on stuff we paid good money for like most sea stars, especially the notorious green brittle star (Ophiarachna incrassata).

Dr. Rob Toonen has written a nice article on them here. Please note that the editors of that online magazine did not catch the many misspellings in the photo captions, which were probably not reviewed by Rob himself before publication. Some hobby authors have a habit of misspelling the name of the genus as Linkia. It's not Linkia, it's Linckia, after J. H. Linck, an 18th century naturalist who wrote about sea stars in 1733. A couple of the photographs misspell the species Linckia multifora as Linckia multiflora. It's multifora, not multiflora. That mistake keeps getting copied over and over again because a couple of hobby authors misspelled it originally and it is usually not noticed. It bugs me because there is a huge difference between flora and fora as anyone who ever studied Latin would know. <End of nitpicking.>