What are these?

[reeferericb]

I have two different crawling things in my tank (several of each color). One looks white and the other black. I can’t tell if they’re the same thing (make/female) or two different species. Of course I’m also curious if they’re good to have in the aquarium as well. Thanks

 

[T-J]

Stomatella.

 

[reeferericb]

There’s a few vermetid snails in the tank as well.

 

[reeferericb]

Stomatella.

Both types are stomatmella?

 

[T-J]

Both types are stomatmella?

Yes. I also have black and grey ones. They look like snails but have a thumbnail shell on their back.

 

[Baneston]

Both types are stomatmella?

Oddly… they are one of my favorite things to watch. Sometimes I go days without seeing them do too where ever they are currently cleaning.