Gearing up for 90 FOWLR

Im getting ready to start up another tank soon.
I have a question, should I go right for a refugium like I used to have made out of my wet dry sump, or use it with bio-balls?
Last saltwater system I had I converted the sump into the fuge but I had corals. This time I am doing FOWLR so Im not sure what I should do.

 

Also, I have a mixture of 50% crushed coral and 50% sand from my past setup.
Should I use that for my substrate?

 

Fuge. IMHO the closer to all natural nutrient export the better any system will be.

 

i am guessing if it is a FOWLR that you will have more carnivorous fish so it will be dirtier than a reef, in which case i would have a skimmer and not use bio balls since they are usually a nitrate trap.

 

Yes, I have an Excalibur skimmer that will be used. But actually it will have reef fish. I also intend to stock lightly.