Storing B&W film chemicals

[Steve Ricoh]

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Just getting into the old B&W home development... parcel contains the chemicals just turned up.

Q Where do you store? Thinking about temperature effects, esp. in warm weather conditions, eg summer, or central heating in the winter.

I’ve had thoughts about using the fridge but most of ‘my space’ is taken up film. 🤪 Also, Mrs would be less than chuffed, I guess!

[Herr Barnack]

I store mine in our basement, which is cooler than the upstairs. 

If you use the brown plastic storage bottles and keep your chemicals at or near rom temperature, they should be fine.

[250swb]

Under the kitchen sink, it's a stable temperature year round and the chemicals only ever need warming or cooling a couple of centigrade.

[adan]

B&W Fixer and stop bath are quite stable at any temperature that you are happy to live in. 15°-25°C

Stop bath is acetic acid, which is essentially already-oxidized ethanol (you know, fruit juice > wine/cider > vinegar/acetic acid). Not much that can damage it except baking soda or other alkalis.

Fixer is a generally a mix of acetic acid and sodium thiosulfate, and is good for 2-3 years. The main problem with storing partially-used liquid fixer lies in the fact that it accumulates dissolved silver-halides that it has removed from film/paper, and which can precipitate out as a muddy sludge of silver sulphide (good for recycling the silver; nasty stuff to get on your film and prints). I stir up/shake the bottle if it has been a few weeks since previous use, and pour out a sample. If it is gray with sludge, I toss it into my 8-litre "collecting bottle" to take to a recycler, and mix a fresh batch.

Developers, however, generally contain organic compounds - as occur in living creatures and foodstuffs - and thus can spoil or rot fairly quickly once diluted in water. They are the most sensitive - a matter of hours to weeks depending on the exact formula and concentration. But the undiluted "stock" solutions shipped from the factory do better (Rodinal/HC-110/TMax/DDX), and powders better yet. I have undiluted Kodak HC-110 "syrup" that is at least 18 months old, and still performing like new once diluted 1:31.

The old "stock solution" standbys - ID-11 or D-76 or Dektol - usually acquire a fairly strong "halitosis-like" stench if they are on the verge of going bad.

Wetting agent (e.g. Photoflo and such) for spotless film drying is not especially reactive just sitting in a bottle. It is essentially a simple detergent without scent or other additives. But I have occasionally had something biological grow in it after several weeks, once mixed into its very dilute version for use. So I check it before every use for "transparent gooey specks." Or simply toss it if I can't recall how long it has been mixed.

In most cases, powders that have not been ionized by dissolving in water, and kept sealed against humidity, are pretty stable.

I do store my bottles under the powder-room sink where I process film - as Steve says, reasonably stable temperature, and very handy to pull out for use.

Generally, photo chemicals should NOT be refrigerated once in liquid form. It can cause some of the dissolved chemicals to precipitate out.

Edited July 31, 2021 by adan

[Danner]

I store my dry and liquid chemistry at room temperature in a cabinet, maintained at about 21-24ºC.  Film goes in the freezer.  For dry chemistry, I've had stuff for 10 years that was still fine to use.  Liquid chemistry, I try to use it within a year of purchase, and within 2-3 months once the seal is broken.