My first batch of wine has fermented in the plastic bucket, racked to a 5
gallon bottle with air lock, and racked to a 4 and a 1 gallon bottle both
with air locks. It is coming up to a month and getting ready to be racked
again. Most of the solids in the wine has dropped to the bottom. The wine
looks very much cleared.

When I rack this next time I will have less wine than I do now. I am
planning on topping the 4 gallon bottle up from the one gallon bottle.
Should I refrigerate what is left from the one gallon bottle to keep for a
topoff for the next rack? If I refrigerate, do I need to find a bottle that
will fill to the top and drink the rest?

Or should I find a bottle that will fill to the top and just cork it until
the next rack.

Will I still need to but the air lock on the 4 gallon bottle?

Should I use CO2? If so what is the best way to apply it?

Roy