What are these things?

Hey i got a few pics wondering what these critters are:

 

First let me say that you have some of the best pics for identifying these things. Usually you'll get a very blurry small pic. Thanks for that. The first pic looks to be an asterina starfish, they generally good, but can be a nuisance if the population gets out of control. The next pic is bubble algae. Don't pop it in the aquarium. Take the rock out and scrub it a lot, you also have some green hair algae. You are right in the the worm is a bristle worm. Some people like them others don't, although a member here just had a larger one eat several of his corals, I wouldn't want one in my tank. The last two pics appear to be different varieties of coraline algae, it's nice and colorful and is greatly in demand for new hobbyists although it becomes a nuisance when it starts growing all over you glass.

 

couldn't of said it better myself...but if you dont wanna scrub ur rock to get rid of the bubble algae you can get an emerald crab, for the hair algae i recommend Sally Lightfoot crab...they are like ninja's on hair algae

 

oh and as for the coralline....enjoy it while its new...you will be cussing at it in about 6 months.