What is that thing? cowrie?

[Icefire]

It's nocturnal, currently breeding (aquarium up and running since 10months) and I have at least 3 adults, a few baby.

They look like they eat film algae.

http://www.icegecko.ca/aqua/id01.jpg
http://www.icegecko.ca/aqua/id02.jpg
http://www.icegecko.ca/aqua/id03.jpg

[demonsp]

Stamatella snail .Look here. http://www.melevsreef.com/id/

[Icefire]

I was thinking it was maybe a nudibranch..

but stomatella Varia look like a good candidate and something good for my reef