Question on hitchikers

[mot ii]

One of the newer LR pieces we got has what appear to be a couple of hitchikers and I am hoping someone can help me identify. Sorry the pics aren't the best so if you can't really tell... that's okay.
The photo with area circled shows two very small things that just very recently showed up. They look like really tiny snails although right now they appear to be more "attached" to the rock and almost like 'growths'. There is a third now starting... it is really small (can't see in pic) and almost all white right now. I am thinking they kind of look like "Collonista" snails - the coloring on the two are almost that pattern. Would this be characteristic of the growth of such a snail?
The second photo is one of a large portion of our 65g tank. On the same LR as first photo (large one near right hand side) there are two things growing hear the bottom. They are right by the 'date' on the pic. One is kind of cream colored and appears to have something similar to sponge holes although the holes are not open. The other one is a bit smaller right now and green in color but appears to be growing similar to the first one.... any thoughts?

 

[farslayer]

That first pic looks an awful lot like sundial snails. Search for them here and see. If so, get them out, they feed on zoanthids. Second pic looks like sponges. Both pics are hard to see, so I could be wrong.

 

[mot ii]

Thanks... yes they kind of do look like the sundials... but the coloring on mine is a lot lighter (a very light tan/brown). That's not to say it won't darken over time. Sounds like I may want to get them out though in case we ever put anything in that they will destroy......

 

[ophiura]

They are not sundials, they are Collonista (google collonista snails) and are very good

 

[mot ii]

Whoa... I went back downstairs to look more closely at the 'snails' and when I turned on the tank light and started to look around... I see that they are not "attached" but are moving around.. and they are not just two/three... there are quite a bit more of similar and smaller sizes. Where the heck did all these guys come from??!!

We had also gotten a few feather duster worms as hitchikers on a piece of dead coral we bought two months ago...and they seem to be multiplying on that coral now.
I also found a 'slug' type critter that is moving around on the same piece of dead coral.
It's weird how all of a sudden we have all these new critters... we recently moved around the LR (after having to catch two damsels) so I am wondering if that made them start moving around more??