this answer sometimes angers folks but its meant to help vs anger
not sure of the strain. the important part is its been associated with tank loss/willing takedown due to takeover posts, and you have a chance to act early vs take a chance.
be lifting out each rock its on, use a knife to detail scrape around non targets, pulling back and debriding the algae off the rock like a big tooth sitting on the counter. put peroxide on the former algae spots you made clean already, rinse, put back in reef without X
my advice is to specifically not bother with ID nor adding things to the water to maybe solve it. that's exactly how they wound up with a willing takedown
we have hundreds of these examples already logged if wanted to see before and afters, the recommend above comes from lots of practice. we wouldn't dose vibrant, or fluconazole, because our goal isn't to wreck your system with a tradeoff invasion in three months, ours is an export way.
it is reef dentistry. Im making a new article on it, building up work examples in fact.
the alternative is willing take downs sometimes, and in other times total success as vibrant has killed target algae in many reefs. Long term tracking is where things differ
reef dentistry has the best long term tracking of them all. we're flushing, rasping, avoiding nontarget areas and getting out accumulations using metal tools and exporting, exactly as a dentist does but in a reef tank.