slug id help please

Sheesh now that you've said nudibranch I wonder why it didn't occur to me before. There are all different sorts and they all have specialized specific diets. I've had to deal with some nasty ones that eat zoas in the past. They can come in on anything though, substrate, etc.
 
It can be really difficult to accuratly identify a species just from a picture, while its undoubtably some species of nudibranch i dont know if i would be 100% positive of the species just by comparing pictures. As to how it got into your tank there are lots of ways, remember a stoweaway doesnt have to make the whole trip on your rock or coral, he may have come in on a piece you've never seen and then migrated to somthing you bought out of the same tank at your LFS.
Out of curiosity, what species did you match him up with?
 
don't remember the exact species and i am not searching again. like i said though i haven't added anything in 4 months! so i dunno where it came from. and ps. i found it again still in my qt tank. what should i do with it? i dont like ending the life of any living thing. do you think the lfs might take it? would it survive in a tank without corals?
 
Probably wouldnt survive to long - most of the nudibranchs have such specialized diets they eat one thing and thats it. I would also be carful because lots of them put out some VERY toxic chemicals when they die
I would try taking him to the LFS
 
Looks simalar to a sea cucumber i had.
 
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