The inside of my tank

Okay, so I have a few questions as to what some things are on my live rock.
First attachment is a pic of what I think is a featherduster, but I'm just checking to be safe. Second is some kind of tube things, I don't have any idea of what they are, but everyone likes them. Third is some kind of hair algae, but it just looks like underwater grass more than hair. In the same picture is a polyp of some sort, it's probably hard to tell when it's closed, but if you can ID it for me I'd be grateful, and last is a coral, I think. Its regaining color, or there's just algae growing on it. Thanks a lot!

 

1) Feather duster - good
2) Tunicate - good
3) turf or green hair algae - add astrea snails
4) not sure

 

Thanks!

 

The coral might be some type of montipora, but I'm not really good at coral ID. The polyps look like closed up zoas.

 

I think they're an sps, and idk what zoas are classified as.

 

I believe the corals is encrusting Porites.

 

Google images is showing some stuff that's not lookin' so pretty. So I hope it's not that, but it very well may be, because that's what it kind of looks like. Thanks a lot Corailline, you're a huge help.

 

You're Welcome. Yes not the most colorful of corals that is for sure. Given enough light it's color may get a little better, but they are cream and tan colored for the most part.

 

I thought turf algae was wiry whereas hair algae is more fine in texture. I could be wrong. I have the very wiry tough kind which looks like what you have. Snails don't mess with it but tons of pods crawl in it. Doesn't spread quickly in my system, I've had the same little sprout forever.

 

My crabs have started taking care of the hair that shows up, and this isn't the fine stuff that's showing up, it's like crab-grass inside my tank. So far they haven't touched it. But they've only been in there a few days, so we'll see I suppose.