Help ID this small worm found on glass

[TehBrainz]

I was looking in my tank the other night about 30 mins after daylight switched to moonlight. Worm was about 0.5" in length and transparent. I'm afraid it could be a young bobbit or some other predatory worm. After some initial googling it kind of looks like a Dorvilleidae worm also. I really don't know though. Any thoughts?

First two pictures (blue) are from my tank. Third picture (brown) is from google of a dorvilleidae worm

 

[35ppt]

Dorvilleidae