As some of you may now know, I'm in the first week of making 5 gallons
of blueberry wine from oregon puree. This weekend, I will do my first
racking process.

My question is, when I "top up", should I just use distilled water? I
don't want to throw the flavor off by adding some oddball wine. I do
have a bottle of blueberry wine that I haven't opened yet that I
bought. Should I just use that? Or would water be OK?