Feather Duster shortened its tube?

[bcollett]

I just saw something new... I have a few large feather dusters in my tank and I added a new one recently. i just put the it on the sand it roughly the place i wanted it. Over a couple days i could see that the worm had been working its way down through the sand and under a rock. I guess once it reached the bottom and found something to anchor to it decided it needed to trim its tube shorter. I trimmed about 2 inches off the top. Has anyone whitnessed this before? i just want to be sure that its nothing negative.

 

[jc germ]

i have a large colony of feather dusters and the past week all of them got shorter too but still looks good don’t know why so any one knows??

 

[supertank]

I have dwarf duster that when I got him, his tube was about 3 inches long. After placing him in my tank, there was about 2 inches of the tube showing, but over a course of about 4 months, he trimmed his tube all the way down flush with the sand. He is finally starting to build it back up now. He's added about a 1/2 inch over the last week or so. Still seems to be happy so I figure this is normal for them.
Hope this helps.