This came out when I was dipping my new coral. Should I be worried?

Wow looks like some kind of sea slug.Could be a stomatella, reef safe according to Marc.http://www.melevsreef.com/critter/stomatella
 
Looks like a stomatella to me, I consider them good.  I used to have millions, but somehow they were replaced with asterina stars and collonista snails over time.
 
Thank you.  I wasn’t going to put it back in the tank. I have had unfortunate luck for a beginner of the fun of having to deal with pest in my tank.  Have a great day
 
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