1st - Looks to be the mucus tube of any number of worm species, or it could be the fungal mats that form on decaying organics when die off occurs on such rock.
2nd - A sponge
3rd - Not sure what I am supposed to be seeing, but if you mean the little "sticks" standing up on the rock, that would be a type of algae. Most likely a filament species.
A Hitch Hikers Guide to the Reefs
Chuck