Help with ID

[HossPilot]

Can sone one tell me what the white things are? I could not tell if I should be concerned and remove the rock and scrub them off or just get rid of the rock or just leave them be? Please help. Tank has been established for 9 months, 210 gallon. I have been dosing Vibrant for 3 weeks due to an unrelated algae issue but Vibrant seems to have no effect on them. They are white although in the pics they looks like they are blue-ish.

 

[blaxsun]

It doesn't look like aiptasia, but my only other guess is a small anemone.

 

[HossPilot]

It doesn't look like aiptasia, but my only other guess is a small anemone.

Definitely not an anemone. I peeled it off the rock and it was crusty. I thought it might be some sort of algae or a parasite. Still not sure, just monitoring to see if it grows back. Thanks for the guess. Like I stated, I am still at a loss.

 

[ISpeakForTheSeas]

My first thought would be a sponge (I wouldn’t venture a guess on what kind from the pics, but some Leucosolenia spp. can look pretty similar to this).

 

[EeyoreIsMySpiritAnimal]

Definitely not an anemone. I peeled it off the rock and it was crusty. I thought it might be some sort of algae or a parasite. Still not sure, just monitoring to see if it grows back. Thanks for the guess. Like I stated, I am still at a loss.

Can you post pics under white lights?