I just noticed your location. I would bet money that it likes the dirt because of the extra humidity it provides. The relative humidity there is nothing like Memphis so your Phal is taking advantage of the extra moisture.
I would be willing to bet that your dirt has a good bit of perlite and is pretty loose because it is not humid there.
I would leave it alone and just monitor it. Remember, everyone's conditions differ. It is hot and humid here so we would probably never grow them in dirt.
But if it works in your conditions, no need to stress the plant by changing.
