Redish purple coloration on leaves. What is it??

[lisaxaphona]

I have a decent size phal, about 3 or 4 leaves out of 7 have this red purple coloration, mostly on the tips, both sides, besides one leaf it is just on the top. I have read it could be because my phal has purple flowers, I have read it could be dehydration, I have also read that it can mean too much light, but the green part of the leaves is pretty dark, which I've read means insufficient light. I just bought this orchid on clearence, and it was in fact dehydrated, the roots were extremely brittle. I think since it went on the clearence rack they stopped taking care of it. It was on a bottom bay shelf so it could maybe have been getting insufficient light, it was pretty dark underneath there, so maybe the coloration is just purple pigment? I also read that it could be a fungus but it's not raised or anything, other than the color the leaves seem alright for the most part.
in the photo attached, the leaf on the left is underside, the one on the right is the top of the leaf.
Also, if it is because of some kind of ailment, what should I do to help/fix it? Thank you!