Phalaenopsis leaves mottled

[Roberta]

It looks to me a lot like hard-water residue. If so, you can clean the leaves with a half milk-half water solution, or a bit of lemon juice diluted in water. (use a cotton ball, or cotton swab... softer than a tissue or paper towel, you don't want to scrub) If it comes off, great. If it doesn't it could be pest damage, and you'd need to make sure they're not still around,