Filtration question?

[asylumdown]

FishyFishy is right. The goal with a marine aquarium filtration setup should be to limit the surface area upon which purely aerobic processing of nitrogen wastes occur. It sounds counter-intuitive, but when nitrification happens on a live-rock substrate, the nitrates are produced right on/inside a substrate that is more likely to have deeper anaerobic pores filled with anaerobic bacteria that will convert the nitrate to nitrogen gas. When nitrification is happening on a substrate with no anaerobic core (like all the commercial media you'd put in a canister filter) the resulting nitrate ends up in the water column and out of the reach of whatever population of anaerobic denitrifying bacteria you might have in your rock and sand.

If your'e going to have a canister/HOB filter, you should fill the biological media tray with the largest live rock rubble pieces you can fit to maximize the denitrification potential of the rock.