hard shell with what appears to be a worm inside.

[Tohni]

They are all over my tank. If I shine a flashlight on it, the worm (or whatever it is) retracts deep down into the shell.
Does anyone know what this is and if it is ok??
Thank you

Tohni

 

[Ocelaris]

Vermetid snails

 

[Tohni]

Vermetid snails

Thank you are they safe?

 

[Dsnakes]

Thank you are they safe?

I suppose they are ‘safe’, more of a nuisance though. They send out a feeding string of mucous that will irritate corals. They also will multiply somewhat quick. I took out as many as I could with bone cutters.

 

[KMench]

I suppose they are ‘safe’, more of a nuisance though. They send out a feeding string of mucous that will irritate corals. They also will multiply somewhat quick. I took out as many as I could with bone cutters.

Agreed. They can turn into a pain and reproduce quickly/irritate your corals to the point they stay closed and don’t extend polyps.... or they can be no big deal. Depends on nutrient levels etc etc.

 

[Ocelaris]

The biggest danger is to your fingers, those buggers are sharp! But they've just been a nuisance to me, and nothing eats them that I've found.