I have done so much reading things are starting to get confusing

But I am going to take it slow before I do anything. I want to start my very first nano and sw tank. 20g aga long. want to get it drilled for an overflow. A 10 gallon overflow +
AquaC Urchin protien skimmer. Here is what I would like to keep as far as coral: Ricordea Mushroom, Blue/Green , Ricordea Mushroom, Red/Pink ,Clove Polyp (purple) , Cladiella (colt coral),
Bubble Tip Anemone;( much later an open brain and one clam) ; Inverts plus one to two fish
Please forgive me for the long stream of questions that are about to follow.
I am imbased to ask all of them at once, but I think most of the answers will depend on the tank setup and coral I want to keep so I will just ask them all at once to keep things in presective.
1) Does the overflow need a refugium?
with live sound live rock/ will I need to keep inverts in the refugium?
2)What would be a good lighting system (everything has a moderate light
requirement except for the anemone)
will over lighting or too powerful of a light hurt things that
don’t need it.
3) What is adequate "moderate" water flow?
4)What will I need to do to feed my tank?
I know that some coral will just need light but how do I find out what I
will need for the ones that don’t.
Thanks guys,
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