So today I was moving some coral out of my DT and in to my Frag Tank. I dipped the coral and I noticed this worm. It is about the length of a pinky nail. Good or bad?
Looks like a bristle worm to me. Opinions are usually split on whether or not to keep them. I've seen people say they can multiply quickly if there isn't any predators to them in the tank. I only ever seen one in my tank and I pulled it out.
It looks like a bristle worm to me as well. These are generally harmless IME, but a lot of people tend to freak out when they see them. They're actually one of the best CUC members you can have in your tank to tell you the truth. GL.
If the bristle worms get to the point of bothering you, you could ad a wrasse. They can keep them in check very well in my experience and are a great colorful flash weaving in and out of rock work.