I haven't had Rumtopf in 20 years (since I was in Germany). So, I'm
going to make it. I've been through the FAQ, and have surfed my way
through a mess of posts, but still have a few questions..

1) Some folks mentioned leaving headspace so juice doesn't boil over.
Is this a true ferment that will foam or bubble up? How much headspace
is recommended? Some folks mentioned not making it airtight, but others
mentioned it had to be airtight. Making it airtight stands to reason so
that alcohol doesn't evaporate... but... if it *IS* a full ferment, it
may need to expel fermentation gasses. Anyone care to walk a newbie
through these considerations?

2) Mention of Rum proofs was all over the map. After having gone to
the local liquor outlets (the largest stores here), basically everything
was 80 proof. Some posts mentioned using 80 proof was OK. But, in some
posts, it has been said that it needs to be 108 proof and that anything
less than 100 proof will leave mushy fruit. Thus, I can mix an 80 proof
brand with Bacardi 151 and come close. Does anyone want to discuss the
fine points of proof and their effects on final product?

3) As I am obviously getting a late start, I won't be able to add much
quality, in-season fruit. However, has anyone used frozen fruit? If
so, is there anything special I need to do?

4) How much covering in sugar needs to be done?

5) Containers - traditional container is the Rumtopf, however, I'm a
little leery of the acids and alcohol working on the glaze. Am I ok
doing this in glass?