Anyone know what this is?

[asylumdown]

Started out as one tube, multiplied to a dozen since I've started broadcast feeding the tank with coral food. They look like super teeny tiny tube anemones with iridescent green polyps. They are definitely inside a hard skeleton, and don't look like any feather duster I've ever seen before. They're quite pretty, but with that aiptasia for scale, you can see how small and hard to photograph them they are.