Yes that above is not coralline or calcified growths for whatever variable sat them there.
The mode of control here is the same with every tank invader you'll ever see in reefing. Do we want to farm it on purpose or not
If yes, leave in place. Strangely, people do this with highly risky species like valonia, whatever works lol
If not, lift out any thing from the water with an undesirable, and attack it outside the tank such that it does not exist in that spot, repeat as needed. always see every algae problem tank ever posted on the web as a purposeful growth farming event led by a keeper who either didn't know the opt out option or didn't select it due to one or more perceived constraints. It's both offensive and amazingly powerful algae control mode of thought for ones investment $$ to see all algae as optional, all the time. We have known methods to kill any invasive algae, to not harness them is to simply farm something on purpose. That thought mode is the secret to never ever ever having an algae problem and we apply that to fix algae challenge tanks.