Barnacle on Cerith snail. Good or bad?

[Jorda320]

Hi. I just noticed this odd looking snail in my tank. It does look like a barnacle on top of it's shell, and I do notice a little black tongue coming out of it on occasion. It i on one of my larger snails and is about 3/4 the size of a dime. I've never had anything like this before and I just wanted to ask if I should leave it or remove it. I'm not sure how these reproduce and I don't want anything getting out of control in the tank. Thanks in advance.

 

[BloopFish]

That is a limpet-like snail called a hoof shell. It eats the poop of the host, but it does leave an indentation on the shell. Harmless.

 

[Jorda320]

That is a limpet-like snail called a hoof shell. It eats the poop of the host, but it does leave an indentation on the shell. Harmless.

Wow, I never even knew that was a thing. Thank you very much. Cool little addition to the tank!