I was checking out a friends tank this morning. C He had a Blue Linckia Starfish, but it was doing something peculiar. 
Is that thing eating a worm, a nudibranch, or is he throwing up his guts? The guy who owns the tank had never seen this before.
-Josh
How long had he had the seastar? Linckia are very difficult to keep alive. They may do better in a high oxygen system, but should never be lifted into the air. They are MUCH more intolerant to swings in water chemistry then MANY acropora and pretty much all other sea stars commonly kept in aquariums.
In my personal opinion no LFS should be bringing these in unless a customer with a thriving well established reef aquarium has requested one or they have a slew of customers capable of keeping them.
I can’t tell you how many of these animals I have watched pass away.
To answer your question specifically and unscientifically… It’s taking a dump. Sea urchins = in one end out the other(top), sea stars = in one end and right back out. That’s one huge dump so most likely it was eating something that wasn’t really that nutritious for it.
Hope this helps.
::hitsthefan:: lol I’ll inform him. …and I wanted one too, all the pretty ones are so difficult!
Not all the pretty ones. Heck I love my nuclear greens and purple death palys and the crappier the conditions the more they love life. One of my other favorites is my Sarcophyton leather. Not all the pretty ones are hard.
We know now to read up before purchasing right? 
wasn’t my purchase, but I certainly have already learned that lesson. However, just a note Gordy, those Carnations are still as alive and gorgeous as ever.
What a hobby!
I heard you say it was your friend. Just this is another one of those items impulsively purchased more then it should be. Call me preachy, but just wanted anyone reading this to know there are many animals out there that many of us may not be ready to keep. I wouldn’t touch a linckia at this point as there is not enough for it to feed on in my tank and my chemistry has been too shacky for my liking. I’m also considering adding a second skimmer just for gas exchange purposes.
Very glad to hear those carnations are doing well. What is your feeding regiment like? They can actually handle higher nutrients levels from what I’ve heard as long as the rest of the chemistry it rock solid. Many people who keep them well have low lighting and not many scleractinians. This way they can allow the nutrients to get higher with out an algae bloom or harm to many animals in teh tank.
They both get low light, and my pink one is hanging upside down, it seems to dig that. They have their moments when they shrivel up a bit, but they always turn around. I spot feed everything with a baby medicine dropper, they get phytos and oyster feast about two to three times a week.