I already asked this question two months ago on the B&W film, paper, chemistry forum before realizing that it could be asked directly here :
I bought few bottles of Adostab few months ago and I'm finally about to use it for my films. My only concern is : Adostab is supposed to be Agfa Sistan's equivalent and I've read in the french magazine Réponses Photo Agfa Sistan's review that Sistan longevity, once diluted, is only of 24 hours. Could you confirm me whether or not it's the same with Adostab ? I have a lot of films to be developped but unfortunately I don't have a drying film cabinet yet, so I'm limited to 3-120 or 5-135 developed films as a maximum per day as I must let the films dry in the bathroom overnight. So does it mean that I´ll have to use freshly diluted Adostab for each development or so ? And what about the stock solution ? Do I have to keep it in collapsible bottles to prevent oxidation or does it keep its properties without particular care like, let´s say, Rodinal or ,even better, a stop bath ? Does the film leave some silver in Adostab as with developer and fixer ? Seems very unlikely to me, but I'm no chemist, that's why I'm asking...
I'm asking all this because there's no way, for me, to detect whether Adostab/Sistan has done its work or not.
Grossly, when I do something wrong with the developer, I'm usually able to see it right away when the film is drying. When I do something wrong with the fixer, I will know I did after few years, even if if the film is ideally stored. When the whole film processing is done perfectly with fresh solutions but without Adostab/Sistan and when ideally stored, it should take few centuries before the film shows few signs of deterioration. And, if I add Adostab/Sistan in the process, the picture/silver halides crystals should survive (?) the film base. At least, that's what I'm hoping for as I won't be there to verify...
Sistan, Kodak Photo-Flo and other final rinse agents have a short life once diluted due to mold and bacteria. As a stock the detergent is too concentrated for stuff to grow in. Once dilute it is like leaving a glass of juice out, it will have stuff growing in it in a very short time. But it really is not an issue as these agents are cheap only a little is used per session in the darkroom. A single bottle can last for dozens of batches of film.