Wird Critter ID please

[CoralsAddiction]

Hi,
I noticed today this weird critter releasing substance from it's mouth.
The critter itself is on the bottom of the screen while the released substance is more visible over my soft coral colony.

Thanks in advance
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[Johniejumbo]

Kinda looks like something spawning maybe. Is it stationary? I think I’ve seen some type of snail do that before but I’m not certain. Maybe someone else will chime in that’s more useful

 

[CoralsAddiction]

Here's a still image of it

 

[CoralsAddiction]

Kinda looks like something spawning maybe. Is it stationary? I think I’ve seen some type of snail do that before but I’m not certain. Maybe someone else will chime in that’s more useful

After doing its thing, it crawled under the coral/rock.

 

[Johniejumbo]

Hard to make that out in the bluer lighting. Got a flashlight you can shine on it to get a better look?