small worm in coral (spionids?)

[giganojonis]

Hello, I'm wondering what kind of worm(?) this may be. They seem to come out at night and live inside the coral skeleton. It retreats back into the crack between the plug and lepto when disturbed. I also see a few living in my cynaria skeleton. I'm not sure if it's a spaghetti worm or spionids because I only see individual worms and they live in the coral skeleton. They don't seem to bother the corals yet, but I had to manually remove a tube poking out of my cynaria when it arrived which left a hole next to its mouth (which may be a different critter). Thanks!

 

[Aboynamedsous2]

I can’t see well in the picture but have had first hand experience with both worms. Based off my knowledge it’s not a spaghetti worm the worst they do is build sand tubes on the colony and irritate it. Is it’s a spinoid worm it will have a hard tube with a little wire like tentacle sticking out the way to kill it is to glue the top of the tube shut ( always use aquarium glue). They look similar to feather duster worms but only one feather. Here is some photos for reference: