I would use a 4-6 inch Sand base, and 1-2 LBS of Live Rock as The Bio-Filter. The combination of the two will collinate all the bacteria you will need to break down waste products left behind by the tanks fish, and other critters. You should also Have A good Protien Skimmer. I like the Aqua-c Remora. It is a 18" Hob
model and lists Here
for 163.95. This will remove DOC
's. I just recently purchased a Skimbox Found Here
. It will help skim the surface of the water were oil like slic forms from Doc
This should be all the filter you need. you could also sset up a Refugium
Too if you wated. They also serve a purpose in cleaning the water of waste.
Hope this helps. Good luck! 8)