What are these? newfound hitchhiker

[j.r. 1221]

My tank has been running for a couple weeks with approx 90 lbs of already cured live rock. My ammonia, nitirites and nitrates have been at 0 for a week now. I had a slight increase in nitrites for a couple days but ,as mentioned, have dropped to zero.
I have spotted a small bright green feather duster, a worm that pops back into the rock when I shine a flashlight on him.
The one thing I can't find in any hitchhiker threads, so far, are 5 seperate clear/white colored polyps. I can spot them all at night with a flashlight but only 2 seem to stay out all the time. They are small. Maybe the size of a pencil eraser on a thick stalk. However, I am still waiting for my light fixture so the only light they are receiving is the window that the tank is next to. Originally I thought very small aiptasia, but they don't quite look the same

Can't seem to post my pic, I'll try again later.

 

[j.r. 1221]

bump.
I just spotted a small crab. He is very plain, brown in color.

Just when I start planning the snails I want, now I'm worried this little bugger will make a snack out of them.
I'll try again tomorrow to post pics.

 

[cedarreef]

It might be a gorilla crab which will kill inverts and small fish. a pic would greatly help identification of all hitchhikers.

 

[j.r. 1221]

Just spotted this little guy again with my flashlight. Thank god he isn't hairy .....and he doesn't have black claws. I was able to get a better look at it and watch it for awhile. It is actually a dull green and was cleaning the rock. Oh please, let it be a "free" emerald!

 

[j.r. 1221]

One more try at posting a pic.......