As BBB pointed out, a pump helps this, but you needn't have an air stone. For whatever reason, having the water circulating in the stew seems to aerate the solution as well (or better) than an airstone. So say the Dutch, anyway.
As far as letting the pots dry: each watering does not saturate the medium, so by watering each day or multiple times per day, you're really after a consistent water content, not saturated and not dry.
The plant wants an optimum ratio of water to air in the soil. The problem with traditional watering is that you are constantly either too wet or too dry. The plant will tolerate it, but it's certainly not ideal. Letting plants consistently wilt from over or overwatering, for example, is a sure way to stunt growth. This is why drip irrigation - be it hydroponic or soil - is a good way of maintaining balance. This explains why systems that maintain exactly consistent water content - wick systems - are (in my opinion) the ideal.
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