Critters Getting Along?

[MMAX]

I have quite a pile of critter in my tank, some which I have added and the majority that came out of my live rock. From what I have put in I have a few hermits, a couple of snails left (the hermits seem to enjoy dining on them), and I added 2 cleaner shrimp yesterday. What came out of the rocks are a dime sized white hairy crab, a couple of white shelled snails which live under the sand, a few colonies of fan worms, a pile of copopods/amphipods/isopods, some vase shaped things which I don't know what they are and 10 or more sea slugs. What are the chances of everybody living happily in here (aside from the hermits and the snails)? Also I recently noticed on one of my rocks a clear anemone type thing. I've read about glass anemones and that they are bad hitchikers. If they are these, are they harmful to other creatures?