What be this?


Active member
not a fish disease, but I didn't spy a common reef pest forum so I'll give it a whirl here


i seem to have acquired a decent number of them suddenly. they do move around a bit so i'm guessing worm of some kind?

what's most odd is my two halichoeres wrasses don't seem to be interested in them. i've seen them cruise up and look at them, but then move on without demolishing


Active member
hmm the only thing that slightly resembles them is the sea slug vayssierea, which says it's good :unsure:

idk if they're even bad, i'm just shocked the wrasses don't mow them down..


Well-known member
I think the glob would love a shot with the white lights on, it would help ID for sure. If you see them tomorrow morning try to get the whites on and a picture snapped as I am now following along with this one too!


Active member
hmm, so seems to range from whatever to possibly bad?

the ones i'm seeing are pretty tiny, like 1/2" at best when fully stretched out


20 Year Noob
I always judge inverts as innocent until proven guilty. Especially if you are collecting them off of glass and not coral soft tissue. Both of the animals mentioned by @The Gob are not well known, but are very similar to Spaghetti Worms or Medussa Worms, which are very much beneficial to our tanks.

I don't think I would consider any of these animals, a priori, as a decided risk factor for any aquarium inhabitants. Neither, however, would I consider them as benign. I like nemerteans and consider them very neat creatures, but I would not risk them in my reef aquarium.
However, based on that conclusion, I would probably remove them.

The Gob

As of now I wouldn't worry simply b/c they're easy to catch. The skilled predators that you really don't want in your tank aren't getting plucked out with tweezers.

If I had to guess the ones pictured eat other worms or pods- not enough to make any difference one way or the other.