His last paragraph is pretty important in consideration of the article.
"In a nutshell, it is best to use the air stone and air pump combination for hydroponic methods like Deep Water Culture, and if you choose to use it in another type of hydroponic system make sure to place the air pump in an uninhabited, well-ventilated room that is not enriched with CO2 (people hanging out in an enclosed space increases the CO2 levels). Dissolved oxygen levels in systems other than DWC are best maintained with the addition of a stirring pump. If you follow these recommendations you may save your plants (and your conscience) and become a more successful gardener in the process."
For the most part DO is absorbed by H2O only as it comes into surface air, so in order to highly oxygenate your H2O, you need to increase your surface area (not practical for most hydroponic situations) or you need to move the H2O faster to the surface increasing its ability to absorb O.
In most hydroponic situations we opt for using "bubblers" of some sort as they can move quite a bit of water without heating it as most water pumps do.
An interesting article I read somewhere on this site, brought up research that very very small bubbles that collapse beneath the surface of the H2O not only release their O into the H2O but there is also a small electrostatic charge released that the researchers believe is responsible for measurable increase in yeild.
