Question
Hi!  recently purchased a large phalanopsis plant from my grocery store. When I brought it home I realized that there was many white stains/marks all over the plant's leaves. I tried wiping it off with a moist towel, but when it dries the marks all come back again. Do you have any idea what this is? Is there a way I can get rid of it?

Answer
Victor, the white marks are likely a calcium deposit from hard water.  Suggest you try a bit of vinegar wiped on the affected leaves. Depending upon the thickness of the deposit, you may need to repeat this application. Vinegar contains a weak acid (acetic) which can dissolve the calcium without damaging the leaves.