I see very little in terms of live roots in the image provided. In my experience there is no need to fertilize your orchid until it begins to recover two to three months down the road.
This Phalaenopsis should be repotted yearly, every two years at most. Ms. Doe has provided you with excellent advice. It will mean a good start in bringing it back to good health.
Epiphytic orchids make good houseplants in many cases. Epiphytic means growing upon another plant for support. As was mentioned, this orchid needs an open mix, NO SOIL.
