Need advice/help with sick Phal

[urszula22]

This is the first time I came across a Phal like this... I need some advice as to what I should do. I bought it yesterday and the first thing I did was repot it since it was in tightly packed moss... I did some research and actually found out that what it is, is a terminal spike. I cut off the dead roots and potted it in bark. Should it get plenty of light? Should I cut off the spike? Fertilize it? I don't know what to do from here, and I don't know if it was a good thing that I re potted it... any help would be appreciated thanks!