Redish purple coloration on leaves. What is it??
 

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!

I would lean towards it got a lot of light (getting to it being too much) - only because of the end of the upper side of the one leaf showing it. But, I'm interested to see what others think.

I was thinking they must have been positioned in such a way that only the tips got the really bright light.

Thank you guys. The bay shelf was like wired for the shelf floors, it was a center unit, so not pushed up against a wall. The heath orchids that weren't on sale were on one of the middle shelves, with certain other leafy plants above, as well as in front, parallel. (Like a really small grocery isle where the path way is only 4 feet wide). The lig ht was definitely compromised from all the leafy plants surrounding the orchids.
My question now, should I keep it in moderate light and slowly move it away, or keep it in low light and slowly move it to more? My situation now where I keep my other phal is in an east facing window, with the blinds always drawn and turned upward. My other phal has beautiful green leaves, but this one I got on clearence (I am a nurturer, mom always told me to stop bringing home broken boyfriends ;) - about a week before this one, so I still haven't found out if they are fine with this light or want more.
I found out today it's too dry for this guy's aireal roots, they decided to shrivle.
Anyways, thank you for your help, I will post uodates/pictures, hopefully things improve.

I would just put it where you have the rest of your phals. It is out of the situation that caused the change, so it should be ok.

Purplish or red coloration from high light doesn't hurt plants. If the light becomes more intense they might burn, so the purple can be a warning that it's getting near the danger zone.

I have a solid dark purple phal and it has purple reddish pigments through out the leaves. Mostly on the undreside of the leaves. It looks like freckles. I wouldn't worry too much about it. As long as the rest of the plant looks healthy, whatever issue it has now will self adjust.

I forgot to mention in my first post that one of the leaves tips was dead/burned. It was only about half an inch or so not much at all. I cut the tip off just to be safe so it didn't die more, at the time I wasn't quite sure if it was burned or something that was killing the leaf. It also had this coloration towards the base of the leaves in the crown area. Thank you for your time, when I repotted it there were only two or three root ends that were actually dead, so I am pretty happy getting such a healthy orchid for $4!