From what I remember there are two kinds of chocolate bloom. One is when the chocolate gets too warm and the cocoa butter seperates, the other is sugar bloom when the chocolate is stored in a too humid environment and then the moisture evaporates from the surface - like storing in a refrigerator or freezer.
Humm - you need a cool dry place. Maybe it could be stored in the refigertor if stored in one of those HandiVac vacuum storage bags ... I don't know, I never tried it.
"It ain't what you don't know that gets you in trouble. It's what you know for sure that just ain't so." - Mark Twain