Too Many Questions 2 List

I'm fairly new at this. I'm in the process of setting up a Natural Reef Tank
(75 gal.) From speaking with various other hobbyists I've been told the
following:

use a 2 - 3 inch sand bed

Protein Skimmer
1 power head
1 power head to cause turbulence
Live Rock (duhhh)
No other filter at this point is needed.

R*O*D*I* for the water

What I am looking for is this: So far am I doing ok with what's listed
above?

Secondly:

Sump or not to sump? I have a 20 gal I've been using as a hospital tank
but can be used.

What else am I missing?

Thanks




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