Another ID with picture

[Havoline]

I found this today in my tank, i have removed it until i figure out what exactly this is. All i can say it is a sluggish looking thing. But when i first saw it, it was on top of some rock, stretched upwards and either spitting, vomiting, or burping or something straight up, what was coming out was a greenish slim like bubbly substance. It is very hard to describe what exactly i saw. But below are the pictures. One is of it climbing down the rocks, the other is of it reaching upward and doing whatever it was i described above. This picture isnt the greatest, i had the camera on auto focus and it focused on the limpet, it is the thing kind of blurry behind it. Thanks in advanced for the help.

[Mangodude]

Might be some type of nudibranch.. Hard to tell from the pictures..

[noahm]

look at these. looks like some kind of worm to me, but without seeing it in a really good pic, I have a hard time guessing. Look through the link, and see if you can narrow it down to a family, taking into consideration that there is a lot of variety even among the same family or genus. Try use features like scales, number of antennae etc to narrow it down. If you can get a better pic, I can do a bit more digging.

http://www.chucksaddiction.com/hitchworms.html

Edit: After looking at the first pic, i think it is a stomatella. Basically a slug with a very flat shell. Great hitcher if it is.

image search (http://www.google.com/images?q=stomatella&um=1&ie=UTF-8&source=og&sa=N&hl=en&tab=wi&biw=1033&bih=602)

[SushiGirl]

Stomatella snail. Great algae grazer. It was probably spawning.