Good or Bad?

I have a thing that looks like a snail without a shell living on my rocks...it is black, about the size of a half a pistachio shell, and moves a nd probes with 2 antenii like a shellless snail...never seen him before...is he ok? or should i yank him?

Google Stomella snail, if that's what you have then it's a great member of your cuc.

I agree, it sounds like a stomatella snail.

Yep...thats him...must have hitchhiked his way into tank, I havent added anything in months so he has been doing a great job of hiding. Funny cause he is right out in the open and is moving alot. I did rearrange my rocks last water change, maybe that flushed him out...funny thing about this hobby, you get pets you don't know you have...thanks for the help...

they multiply fairly rapidly.. I saw one, a few weeks later i have 6 that I have found but more really small ones keep popping up in the fuge...