Is your tank suffering from algae? Does your tank look good? If so, then don't chase numbers.
To answer your question though it's very simple. You must remove organics before they dissolve. We use a number of techniques, often in combination with one another. Skimmer is one. Mechanical filtration is by far the most effective, but only if you change the filter out every couple days. This is why filter rollers are so popular. Changing filter bags every couple days turns a hobby into a chore that increase laundry, not cool in my eyes. I do have one filter bag though and I use it to vacuum the sand bed once a month. Sand beds often become nutrient sinks. Other tactics include using turf scrubbers to grow algae and then export the algae with the nutrients going with it. Same thing with bio pellets by growing bacteria and skimming it, along with the nutrients, out of the system.
Bottom line is you need to remove more than your putting in until you hit the sweet spot you're looking for. If this is a new tank, you've heard it before I'm sure, patience. If you have too many fish, over feed, or feed incorrectly you need to fix those issues.
