Yeah,
First thing I thought of when you mentioned white spots on your acros was AEFW... but it's kind of hard to see any of the typical bite marks they leave.
My next guess would have been the Alk, but your reading of "9" should be fine... UNLESS you recently bumped it up to a "9" over a short period of time, which could result in Alk burn. Have you done any water changes recently?
-Chad