Stuff growing in my feather duster

[mattypw]

I have a Caribbean feather duster in my 20G that is starting to be covered in purple stuff. I don't know what it is, but is looks like strings coming off it (that branch). The feather duster seems ok right now. I'm just worried that it may be parisitic.

 

[charlesr1958]

Possibly the worm's "waste"? A photo would be helpfull if possible.

Chuck