white crumb/white grain looking piece hanging from clownfish

[reef tank 2.0]

I can't get a picture of this white speck thing hanging from my clownfish so I will try and explain the best I can.

I am not seeing any strands of white poop hanging from the clown, but I am seeing a small white speck hanging on to the clown. No matter how much wiggling/shaking it does, the white "thing" won't come off.

If I had to explain it, it's almost like a single piece of aragonite sand.

I'm waiting to see white strands of poop, but I am not sure what I am looking at. Is there anything I should keep an eye on to make it a sure sign of disease, if it is in fact a disease?

If it is a disease, do I need to pull all fish out, or just the infected one?

 

[reef tank 2.0]

I did not see the white thing detach but it is gone. I will see if I see any other issues pop up.......Again, no change in behavior, I'll post if I see anything else.

(note: the clownfish never swims along bottom. Always stays towards the top of the tank..)