What in the world is this!?

[Mini Coop]

changed my filter sock this Morning. And this was in it! Any ideas!?!? I thought it was maybe a stick of some sort, but it was up on the side. I believe whatever it is was dead. No “fins” on the side persey, but looked like a tail and when I moved it it almost had a fish-like body!!!
I started with dry rock and have quarantined for 45 days every single thing including inverts and corals that have gone into my tank! So no idea what it could be! The bottom side was very flat. Didn’t see a “mouth”

This is the bottom side.

 

[KJoFan]

In that last pic it looks like possibly a chunk of silicone that came of some place in the tank. Probably was just excess that was loose and finally came off. Is it black?

 

[Mini Coop]

In that last pic it looks like possibly a chunk of silicone that came of some place in the tank. Probably was just excess that was loose and finally came off. Is it black?

Yep - black!! HAHA - I bet that is what it was! I wonder what it came off of!! That's a little scary!! .
Totally freaked me out - it looked like a little fish! . I feel like an idiot! HAHA

 

[Legal Reefer]

That's funny....made me laugh out loud. Thanks for making my day. Reminds me of something that would happen to me....lol!