black dots

Fowlr tank and im dabbling into corals to see if i like it and gonna be upgrading tanks sort of soon so, got a hammer and this "gsp"(its a branching one i think i dont see them too often) and only on the gsp im noticing these tiiiiny black dots kinda look star shaped but they are SUPER tiny i...

Anyone can help me to identify these black dots? Are these parasites, if so what should I use to treat it? This baby yellow tang is eating happily, and swimming around seems to be healthy so idk what is happening here, might need some help, thanks!