I know that the shelf life for photo chemistry is pretty short once it's mixed, but what about the concentrate that you mix it from?

I'm going to the store tomorrow to get some D-76 & fixer, but I still have some stop bath concentrate, as well as photo flo. I know I can use water, or vinegar as a stop bath, and photo flow isn't needed either, but I'm curious. They have been stored in a cool dry place, away from light.

I know that the shelf life for photo chemistry is pretty short once it's mixed, but what about the concentrate that you mix it from?

I'm going to the store tomorrow to get some D-76 & fixer, but I still have some stop bath concentrate, as well as photo flo. I know I can use water, or vinegar as a stop bath, and photo flow isn't needed either, but I'm curious. They have been stored in a cool dry place, away from light.

The D-76 and Kodak Fixer in powder form will last a very long time...years, probably. I usually buy several packets at a time. As far as I know photo flo will last a long time too. I have a bottle I've been using for just over two years and have not seen any problems. I'm not sure about the stop bath.

The only thing, I would think anyway, that would kill un-mixed chemistry, would be excessive moisture.
But I would agree with Paul, that most chemistry in the powder form would keep for quite a long time.
Brian

Thanks for your thoughts guys.

The stop bath and photo flo that I'm wondering about are both in liquid concentrate form. Both kept in sealed bottles, in a dark, cool basement. Since neither one of them are that important, I'm not going to replace them. Just curious.

I'll test them out once I get a roll or two of film shot.

Hi Michael, I had wondered the same thing myself a while ago and while I couldn't find a good thread that I had found before, here's a quote that should help put you at ease:

As for the fixer, stop bath and Kodak Photo-Flo solution, I've used these concentrates that were at least seven years old. I stopped using them during my foray into digital camera systems but I've returned to use them. They work fine and with consistent results. In fact, the photo-flo I have is over 20 years old, something I inherited from a friend.

I would still test them all first but, I would think at least the stop bath and photo-flo should be good to go. Fixer is easy enough to do a snip test on, just mix up a batch and clip off the end of a roll, stick in a little fixer and time how long it takes to clear. Not sure which fixer you have but, for Kodafix, should be 1 minute for a fresh batch and I usually discard once it gets to the 2 minute mark. CLICK HERE (http://photo.net/bboard/q-and-a-fetch-msg?msg_id=00IWxZ) for a thread I found about D76.

Thanks Aaron. I think the fixer I had was Kadafix, but I'm not positive. I would have to go down stairs to check, and I just don't feel like it. :) There isn't much left in the bottle, and it's a milk white. I don't remember it being that color 2 years ago, so I had no intention of using it. I did pick up a couple bags of the powdered D-76, and the last bag of fixer they had at the store today, so I'm good to go. Now I just have to shoot a fiew rolls of film.