Well every tank is different, but I need to make clear I feed mostly Frozen food -- This food is MUCH less nutrient rich, and you will have a MUCH harder time fouling your water. That said, I feed very heavily. As for nutrient export I'm only using a skimmer. To keep my nutrients up I actually have to dose no3/po4 or my tank will get to Zero/Zero. I keep my nutrients higher than most people on the forums for an SPS keeper, but my tank is also less mature.
The more mature a tank is, the easier time people have running low nutrients. When you first start a tank, in my experience, running low nutrients can be detrimental to your aquarium. It was in my case -- All my corals started paling out, and getting unhealthy.
That said, you don't need to run your nutrients too high. Id say most people end up happy with no3 around 5, and po4 around .05, and that's a good starting point to see how your corals react. All corals are also slightly different in their wants/needs, such as flow, lighting, nutrients, etc etc.