After about 10 or so 5 gal batches that were all sub par, I cut back to 3 gal batches until I finally figured out how to get what I wanted. I think I did about 5 or 6 batches like that, and now I'm back to 5 gal. The idea of 1 gal batches is cool cause you can try all sorts of things and you can do it all on the stove! To answer you question I think the 5 gal container will be ok for primary but probably not for any secondary.