Small Sea Slug Hitchiker, WTD?

[Gwynhidwy]

I recently noticed a sea slug, it doesn't have "horns" like a sea hare, happily munching algae in my tank. He is mostly greyish white with some mottling that is dark brown and burgundy and he has a rather pronounced hump on his back towards the front half of his body. Sorry, no digital camera, no pictures.

Obviously it eats algae, but is it likely to poison my tank if bother by another inhabitant or if it dies for some reason? Should I remove him or leave him be?

 

[TheReefer84]

i think they might be stomatella snails, they are harmless and just help clean the tank. i have tons of them that come out when the lights are off.

 

[Gwynhidwy]

Thank you very much, that is almost definitely what I have. I guess that would be why I haven't been able to find a picture of a matching sea slug! Thank you!