This too is not an argument, but an attempt to clear up what I believe are misconceptions. To begin with running bubbles through water does not add oxygen to the water. Gas exchange only happens at the water surface in a very thin layer where water meets the air. The more you disturb this layer, the more you will add oxygen. In the ocean the waves breaking can cause supersaturation. Something that will not happen in our tanks, but disturbing the surface layer as much as you can will greatly enhance gas exchange. In a skimmer there is very little disturbance of the water to air layer, and it is contained in a small area. Therefore it is my contention that a skimmer cannot function as an aerating device. It is unfortunate that I have seen this argument confirmed, but I can't remember where. However, if someone is able to refute what I believe is a scientific fact, I will happily take it back.
