Id This Sluggy Thing Please

[Kaush]

My mum and brother saw this thing on the wall of the tank, but it vanished within he two minutes it took me to get to the tank. I searched all the rock until i found it and put it in a cup. does anyone have ny ideas what it is and if it is good/bad?

The pictures arent the best but it looks like a sail without the shell(slug) and it has long antenae

 

[Colin_T]

It’s probably a sea slug or nudibranch. Some are harmless and feed on algae, but others eat corals, mainly soft corals. Monitor it and see if it starts eating the corals. If it does, then kill it. Most of the coral eating slugs are brightly coloured and poisonous. Yours is pretty bland and most likely a vegetarian slug.

 

[Kaush]

I dont wanna take any chances, i am going to keep it in the cup. can anyone give me an ID of it and whether i sould keep it or not?

 

[Donya]

I'm going to guess Stomatellid, although the pics make it pretty hard to tell.

 

[GShorty1981]

I got these is my tank they come off my Zoas along with loadsa Nudibranchs grrrr

 

[Kaush]

Yer i got a frag of zoas a couple of days ago, are they bad?