Weird clear tubes on live rock and green polyp coral thing

I just recently (3 weeks) finished redoing my 75 gallon. It was given to me a few years ago with some fake rock, a crappy pc light, canister filter, and a few fish already in it. Well the last fish died and I decided to do the tank right. Anyway, I bought a live rock at Petco about 2 months ago (I know, bad idea) when I was getting my 20 gallon for my sump and it now has these clear tubes growing all over it. They've been there for maybe a month. Here's a picture (if I can figure out how to do this)




I have no idea what they are. They haven't spread to any other rocks and they've looked the same for for the last few weeks.

Got another thing I need help ID'ing also.

I bought a rock with a few coral on it the other day when I bought my blenny. Just seemed like a good deal for a nice size rock covered in coralline that has star polyps, feather dusters, and this thing that I don't know what it is. It only seems to open at night, closes up when the lights come on. There is a smaller red one on the back of the rock. It's the big green thing that is mostly closed up.



I'm more worried about the clear tubes than the coral, hoping the tubes aren't bad.

Thanks for any help.

 

do the tubes have a filament or stringy thing that it lets out and retracts? if yes, it is a vermetid worm. nothing to worry about.

 

I haven't noticed any strings coming out of the tubes, I'll have to look for them. If it is a worm, will they eventually cover all the rock in the tank? I'm not particularly fond of the way they look.

 

99% sure they are sponges. I have some crazy looking sponges in my tank

 

2nd pic:

Looks like just a plain old button polyp (palythoa zoanthid). Nice thing to have. Mine usually open up when the lights are on, and close up when it's dark.

 

Thanks for the responses, glad to hear the stuff on the rock isn't something nasty. I figured the green thing was a button polyp, but just couldn't figure out why it would only open at night.

 

+1 on the sponges, I have some that look exactly like that in my tank.