Starting a reef..

in short i would say that your LFS is giving you bad advice (or at least dated advice). I would try to forget everything they told you and start learning from scratch :)

The absolute best resource for building aquapod that I have found is this thread:

http://www.nano-reef.com/forums/index.php?showtopic=54602&hl=stealhealr&st=0

It won't have every detail you need, but covers all your major areas of concern and will give you a good start point for additional research..

just remember to take everything slowly.. you will realize that there is more than enough to work on in the tank without rushing things.. i could probably work on my 12g as a full-time job if i had the time :) so rushing things can only cause problems which cause much more work for you..
 
as for the boxed ocean water, maybe an expert would have a better knowledge, but in a tank that small, keeping ample levels of elements is difficult because there isn't alot of water.. you want to keep the tank as stable as possible.. i would think that the ocean water would not provide consistent element levels which would cause much more headache for you in testing, dosing, etc.
 
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