What is this worm like thing?


Reefing newb
Bristleworm? If so, good or bad? It's frantically swimming around the tank.




It does not look like a bristleworm.
Also, bristleworms are not know to swim in the water. they crawl on surfaces but are not real swimmers.
Very odd. I even cleaned out my whole tank and washed the sand. I've never seen this in the past 6 months.

It's in the process of some, Salty. I just re-started my whole tank and had a bit of a diatom outbreak, which I'm slowly tackling. Looks a lot worse with the stuff not cleaned off the glass.
That looks like some kind of worm, it doesn't look like and eel to me. I guess your best option is to take it out of your tank and put it in a quarantine tank where it cannot make any damage if you want to see what it becomes later or leave it in your tank and take the risk it could be something good.

Good luck with your decision and I hope is not a pest :).