I know I posted about this once already but I got the answer: chrysophytes but I can’t find anything that looks close to what I have. I don’t think it’s a hydroid either. Maybe a snail?? Or a worm? Or even something like aiptasia? It acts a lot like aiptasia. I don’t think regular algae would retract and it’s spreading. I’m a bit worried about it because I wouldn’t think u can grow corals on top of them?? My tank is only 3 weeks old. Just finished cycling and added clean up crew. I started
having these long before the clean up crew so they came with the live rocks. I really want an ID on this to rest easy.