Conflicting Opinions - Newbie Help

[packisbak1]

I started a new 12 gallon Nanocube Dx 1.5 weeks ago with 10 pounds of LR and 15 pounds of live sand. I have never kept a reef or saltwater tank before and have been asking a lot of questions at a few local fish stores in addition to doing a lot of reading on this site. As a result, I am getting really confused and a lot of contradicting information. I thought I would ask all the experts on the board to help provide some guidance based on your own experiences. All thoughts and information are appreciated. Below are my questions:

1) I was told that I need to add hermit crabs in
order to clear off all of the debris and algae off of
the live rock. I have read elsewhere that snails will
do a fine job and that many people don't use hermit
crabs because they will eat snails. Which is correct?

2) I was told to do a water change at the two week
mark while the guy who I spoke to originally told me
to wait "a few weeks". Which is correct and how do I
know when it is appropriate to start doing regular
water changes?

3) When doing a water change I was told to siphon the
sand bed. The guy who I spoke to last week told me
not to touch the sand bed. My sand bed is about 1.5- 2
inches deep.

4) There is all of this lose "stuff" that is blowing
around on my rocks. One guy told me I can pull it off
while another guy said I should just leave it. What
is the correct answer?

5) How will I know I can start adding hardy soft
corals? Should I add snails/fish first? I am only
planning on having 1-2 small fish but would like to
have some nice, easy to keep soft corals.

6) Will I need to dose anything to my aquarium (calcium, iodine etc.) if I plan on doing regular water changes and only having soft corals? I have read that people are fine without dosing but my LFS insists that I should start dosing immediately.

Any thoughts and advice are greatly appreciated.
Thanks.