Feather Stars are some of the most difficult animal's to try to keep alive in our tanks. They are really picky on what they will eat and a lot of food's are not the right size for them. If someone is trying to sell you one of these you may want to ask why they are not maintaining one of these in their own tank's. Here's more info on these beautiful critters. http://www.reefs.org/library/aquarium_net/1296/1296_9.html
Cheers,
Cheers,