Last May I bought a large bottle of HC 100 concentrate (a 28 oz / 828 ml
bottle, to be precise.) I use it mostly with 120 film, mostly in dilution H,
and I am just now getting down to the last of the concentrate (I mix up a
working solution as needed for each roll.)

For the first few months I left the concentrate in the large bottle, but
then in September rounded up enough small bottles to decant the concentrate
into so it would not be exposed to air.

As I finished off one of those smaller bottles last night I discovered a
thick layer on the bottom ? like something had precipitated out. The
developer was also decidedly thicker and lumpy ? more or less the
consistency of half-set jello, and not the smooth maple syrup consistency it
had when new.

I wound up scraping everything out of the bottle and mixing up a slightly
stronger than usual solution (I usually use 10ml of developer per 600ml H2O
and in this case had about a little over 11 ml / 600). I cut the time a
little and used it with a roll of APX 100, and the results were fine,
perhaps just a tad over developed.

But ? I still have my last 125ml decanted bottle left. I assume it too will
get dark, lumpy, and start to drop precipitate out chemistry.

So what I?m wondering ?

 1.. Is they any indicator that will tell me that the HC 110 concentrate is
bad and should not be used?
 2.. Any idea what is precipitating out? I assume it needs to get mixed
into the working solution.
 3.. The small bottles are filled pretty close to the top, but once opened
it can take several weeks before it?s drained. Even the tightly filled
bottles have darkened. What is the shelf life of HC110 concentrate? I see a
lot of comments that say "lasts indefinitely" ? how long is that?
Any thoughts or advice would be appreciated.

- MCC