Chemical oxidation and vacuum wine stoppers!
Darkroom liquid chemicals, we are told, have shelf lives because they deteriorate with air in the bottle.
Having seen and purchased vacuum wine stoppers (put vacuum wine stopper in Amazon search bar) and used them on glass bottles filled with Perceptol etc., they appear to work well. But the question is is a partial vacuum enough to prevent or reduce deterioration for part time darkroom workers like me? The other question is they say not to be used for non domestic use. I guess this is only because of marketing?
i have to say it is great to be part of this forum - I am not alone!