Weird thing on back glass?

[Bossman]

So, I found this weird thing when I was inspecting my tank tonight. It's stuck on the back glass about mid-tank. I have not seen anything like it before. My wife measured it with a metal ruler at 3/8's of an inch. Doesn't appear to be moving at all.

The first pic is straight on, the 2nd from the side. Don't mind the small patch of algae on the back....

Tank is 2 years old and doing good.


Any thoughts?

 

[Brad Waddell Wrath's Reef]

Can you take a photo under whites?

 

[Macdaddynick1]

Do you have rock flower anemones in the tank?

 

[Bossman]

Can you take a photo under whites?

These are pics under white light.

Do you have rock flower anemones in the tank?

No rock anemones, but 3 watermelon BTA's.

 

[JJ Ligs]

Is that a majano

 

[Copingwithpods]

If not a mojano/glass anemone, ever had/have pom pom crabs?

 

[Fishy212]

What JJ Ligs said. The bulb-ish tentacles look like it to me.

 

[Shawn_epicurious]

I just watched this...

 

[JJ Ligs]

Either way if not ID’d for sure get it out just in case