"Aluminum oxide appears as a powdery white or dull gray coating. As oxidation occurs, it hardens and creates a protective layer over the newly exposed areas of corroded aluminum. The aluminum corrosion process is actually halted by oxidation—the metal won’t continue to deteriorate unless the aluminum oxide is removed. As mentioned earlier, unlike rust, which has a flaky, orange appearance, aluminum oxidation cannot be easily chipped off the metal surface."
Maybe just live with it? I am sure many cannot cope with a bit of bubbly looking paint.
From this very forum: