On Dec 26, 10:39*am, "Geoffrey S. Mendelson"
wrote:
Geoffrey S. Mendelson wrote:

Edwal and others used to make a fixer test solution, I don't know if anyone
still does.

It's amazing what you can find with google. It's called Edwal Hypo-Check
and it's still sold.

Geoff.

--
Geoffrey S. Mendelson, *N3OWJ/4X1GM/KBUH7245/KBUW5379
"Owning a smartphone: Technology's equivalent to learning to play
chopsticks on the piano as a child and thinking you're a musician."
(sent to me by a friend)

But the Edwal, as I remember it, is testing for whatever silver
reduction ability remains. Does not the fix go bad for other reasons
that simply reaching it's capacity? I never even approach capacity....