I think my Nassarius snails are dead?

[carlykush]

I brought 10 home about two weeks ago to help me deal with some algae build up on my sand bed. 8 of which are doing an amazing job and are cleaning up relatively all left over food from the fish. I have two that have not moved nor burrowed into the sand in over a week. I don’t know how to tell if they’re dead and if they are, do I remove them from the tank? Pictures of them are posted. EDIT: After taking the picture of the second I realized there’s absolutely nothing inside of the shell. Now I’m wondering what caused this and how do I prevent it?!

 

[jabberwock]

Do you have hermit crabs?

 

[carlykush]

Do you have hermit crabs?

I do not! These are my only CUC. This tank is relatively new. We only have clownfish, the snails, and 3 Zoa frags. I did just notice hair algae starting too.

 

[jabberwock]

I do not! These are my only CUC. This tank is relatively new. We only have clownfish, the snails, and 3 Zoa frags. I did just notice hair algae starting too.

May not be enough food for them yet. Could have been an old snail. The shock of a new tank may have killed it. There are lots of variables.