Still No Success With Phals

[Cerey]

So after trying what seems like everything to maintain a phal orchid healthy and alive, I still haven't been successful in having one for more than two months.

When I buy one, I would change the media from moss to bark and clean the roots. It usually starts getting root rot a week later.
So sometimes I leave it in moss until I see new root growth. By then it's definitely rotting.
I've tried semi-hydro with no success. The roots rot. And any new roots that had started growing just stop growing and eventually rot too.
I've changed my watering methods along with my fertilizer routine with no positive effects.

The only orchid I've managed to keep alive is a small phal seedling which I'm very proud of.

Anyone else have this problem?