| Skimming will take out some water or water with organics, in saying this it will take out the elements associated with the water it pulls out. So yea it removes some elements that way.
The skimmer will also remove organics (detritus/waste) as solid forms and dissolved forms. It will also remove bacteria and planktonic life forms, which are also concidered organics thier just alive still. In removing the plankton and bacteria you are effectivly removing P and N as they have bound it to thier matrix. Yes you loose a little planktonic life but the vast majority of these froms are on various surfaces on the tank and stay close or attached to it.
Mike |