I'd please

Dave H

BRS Member
I found this today in a fairly new tank but I can't see it good enough to tell what it is. I'm back in the hobby after a 25 year hiatus is it good bad or indifferent


Chris A.

Formally toomanyfish
BRS Member
That’s a nudibranch, good or bad one don’t know unless u get a better picture.
Take it out into a container and snap a picture. I wouldn’t risk having it in my tank by accident
def. Nudibranch. as earlier people posted, impossible to tell you good/bad without clearer picture.

Now; Nudibranches come in thousands of varieties, each of which pretty much has their own diet.
- There are Berghia Nudibranches, they eat aiptasia, they're the good guys!
- There are Zoanthid eating Nudibranches. Bad guys
- There are Acro eating Nudibranches. Bad guys
- etc..

I would assume bad guy, to be safe.. and if you have had issues with Zoanthids lately, here's your culprit.



Senior Moron
BRS Member
Are you talking about that bright white thing? On the post is says that’s just a white thing on the glass? Because I think that’s what everyone is referring to as a nudibranch. Just trying to make sure.


Well-Known Member
BRS Member
A few of my zoanthids have been closed recently, and Tuesday I took a good hard look around the zoas and found not one but two of these guys. Hopefully you grabbed him before he moved out of sight.

Here's a pic of one of the two I took out of the tank