id please

[mermin]

today i was looking into my tank after the lights went out and i found a bright light blue worm that was extremely small swimming around with the current. any ideas on it? my tank has been set up since november and ive never seen it before.

 

[graveyardworm]

Most likely what you have is called an epitoke, it's part of the reproductive cycle of the worm, and that is its sole function. Once it has accomplished it job it dies.