Instead of oxygen i'd recommend trying mist (fog), which is formed by microscopic cold water droplets suspended in mid-air. Fine dust particles get trapped into the bong as mist droplets bond to these object's surfaces, raising their weight until they begin to fall at the bottom of the bong. The result is a cannabis vapor which the lungs tolerate with more ease: the dust gets effectively removed in my setup (i have built it and i evaluated it numerous times too). As a consequence of the filtering action implemented in a bong filled with mist, euh... i'd say that some volatile aromatics are also collected at the top of the bong's chamber, this most unfortunate side-effect causes a noticeable loss of aroma and taste. The bright side is that puting a Mist Maker inside the bong's cavity makes the water toy quite spectacular during its actual use!... I can tell as much!!!
Anyway.
In conclusion, using mist instead of oxygen in a bong where cannabis vapor is mixed with it, i've observed that inhalation is rendered quite enjoyable. I'm one of those people who likes when vapor is made extremely smooth to inhale!