Okay, now I have a starter and need a jar.  Do I need something special.  Certainly can do better than the expensive one from KA.  My big question is does it have to have air flowing or does it need a tight seal?  Can I use a mason jar with the metallic lid?  Can I use a quart canister that has a rubber seal and a small metal clamp?  Maybe it is not that important, but I want to do this right.  Thanks for your help.

New Baker