Hi H.
It's a bonus that you know how you want to stock the tank - this will determine what systems work best.
Everyone has their own favorite methods so you may get different views which may seem confusing, I've always found it best to try to understand the reasoning behind the advice.
A predator tank will have a lot of food and waste going through the overflows so the first stage should be mechanical filtration. You can either put a filter sock over the overflow pipe or put matting or a sponge in the first part of the baffles (something that can be removed and cleaned regularly). This removes the waste so it doesn't need to be processed. Some folks might not think this is necessary but all that food will have to otherwise be broken down to its end form - nitrates and then you have to figure out how to remove that.
Because your tank is a predator tank and much of your waste will be protein based you should invest in the best skimmer you can afford. This should be the primary filtration system you use (besides the L.R.). You can add a macro algae refugium if you wish but most fuges can't keep up to the demands that a predator tank will place on them (the macro won't remove nitrates fast enough).
It doesn't matter where you place the skimmer but the return from the skimmer should feed into the sump before your bubble trap (series of baffles). This will remove the bubble produced by the skimmer.
Well that's a start anyways. What are your thoughts so far?
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