Lightened/yellow? leaf edges on my Phal.

[foxtailskies]

Just got back from a couple days' vacation and I noticed that the very edges of my young Phal's leaves appear to be lighter than normal, perhaps even a bit yellow. The 2 topmost leaves almost look like they have a faint ring around them... my camera isn't charged at the moment, I can add pictures later if needed. Is this a problem?

Culture details... It was fertilized Friday morning with half strength 20-10-20, which I do every other week but it did miss a week or so while I was moving back from school. It's been watered every 2-3 days consistently, is in a northwest-facing window, and is misted daily most of the time. It's also just started a new leaf growth (just noticed Friday, when I left for the weekend), and I did give all my orchids a good soaking this morning when I came home. The other 3 orchids in the same conditions are looking good, everybody's got new growth and no other issues to speak of.

Thanks for any help!!!


***UPDATES****

Sorry about the delay, I've been running around like crazy with non-orchid things since I posted that In the meantime, the yellow edge hasn't really gotten better or worse, I've switched my fertilizing schedule to once a week at 1/4 strength, they get another watering during the week where they're really flushed well with clean water. And now there are pictures





(Sorry about the fuzziness, the nighttime light in my room really tests the limits of my poor camera )

As you can see, there's new leaf and root growth, which I generally understand to mean "happy plant", so I'm at a loss to explain the edging. Any ideas?