I think this will be an ID challenge

[Auston]

Only thing I can think of my be an baby elephant snail. Have not been able to find out what this guy is. He is almost all black flesh with a tiny she'll on top.

 

[hotelbravo]

Stomatella snail. they are commonly a tan or cream color but they do have varieties that are solid black exactly like yours.

 

[Auston]

Ahh your totally right. So much for a challenge...

 

[Dkuhlmann]

Yep Stomatella snail. I've got lots of black ones and a few light colored ones in my tank. My sump is full of them, but my McCosker's wrasse I think snacks on the smaller ones