It depends on whether you just want the airstone to oxygenate the water, or whether you want it to be genuinely "bubbleponic" and power the grow until roots are in the water per the link below.
i'm concerned that if i buy all this and get a good growing system...how am i gonna know if the system is bummed out and sucks...i just think the roots suspended in water and spraying the roots with bubbles will eventually drown the roots...but then again I might just be paranoid