this is one of those problems that keeps me up at night and is so frustrating not being able to afford something better, and everything I do get I find out is somehow worse.
I'd think ideally you'd want an all glass cabinet with something on the outside to keep out light, or maybe a safe with a mylar interior liner? Safeflips are mylar, right?
How do you remove potential chemical contaminants from the air (the kind that go through a HEPA filter)? Would an activated carbon filter help or make things worse and cause carbon spots? I had an activated carbon filter for a few months and it just occurred to me the other day it might be worse than nothing now I'm freaked out about how to clean that off everything.
Is vacuum sealing 2x2 boxes safe or is that just going to cause the paper to outgas sulfur?