Hi John,
I would do some reading on that in this forum. Mason jars sound good but realize that, that amount may last you 10 years? I never bought by the gallon for that reason. Dow says a 2 year shelf life, but i believe you got longer than 2 years. I put my nic in the freezer for what I believe is the best possible storage, but IDK what would be the best for PG/VG. When we store nic we want to fill the bottles as full as possible, so there is as little air as possible. That link in the nic
thread my have some info from Kurt. Also use the search box. Good Luck