I would put carbon on, indeed, forget about RO, tap water is fine.
Did someone break in and vandalize your place? I'm really sorry to hear this, good luck sorting it out.
It's entirely possible that the film is bacterial. People actually do dose vodka into their reefs as it's a carbon source for bacteria to metabolize nitrates and phosphates, and it's a common occurence that if they overdose, that the bacteria forms a white film and the tanks are literally cloudy. But the usual prognosis is that it clears in a day or two and the nitrates and phosphates have disappeared. Soooo ... I've got my fingers crossed for you.