Storing D-76

Hi all
A couple of weeks ago I mixed my first liter of D-76. I developed a couple of rolls (tri-x) with it and stored it in a newly bought storage bottle (like this one). When I wanted to reuse it about a week later it had turned all brown. About the same thing happened with a second batch (both stock solutions of course).
I think a couple of things may have gone wrong:

1. I stored the bottle in a place which may have been too warm (about 22-23 degrees Celsius. Is cooler better?) It was in a dark cupboard though.
2. The bottle may not have been up to the task. The website said 'ideal for photographic chemicals' though, but in any case I've read glass is a better choice for storage (especially developers?)
3. I mixed a liter and put it in a liter sized bottle, but this of course doesn't mean the bottle is filled to the brim. Does 'storing in a full bottle' mean 'filled to the brim'? I guess oxidation may have played a big part here.

In any case I'm now planning on mixing some D-23 myself and storing it in a glass (wine) bottle. I'll use a pump to make it a vacuum. I guess this should be better?
I'd like to hear if you have any comments on what might have gone wrong with the d-76 or if you have any tips on storing d-23 in a glass bottle. Thank you all in advance!

Use some butane (lighter gas) and spray a bit in the bottle, this prevents oxidation. D76 should last at least 2 months as stock I would say.

With re-using your developer, do you develop the film in stock solution and then pour it back in the container for next use?
Or do you develop one-shot, where the contents of the bottle becomes less and less after each use?
In the first case, I have no experience so can't really help you there, but in the latter case it's quite possible that oxygen has had its go at your developer.

I store my 1 liter of D-76 stock solution in 3 empty 0,33L PET bottles (regular soda bottles as they can be found in Belgium as well) and use it 1+1 one-shot (150ml stock solution + 150ml water per 35mm film).
I use half a bottle per film and then squeeze out all the air before I close the bottle with the remaining half of stock solution in it. My chemicals are also stored in the dark, not sure if this is absolutely necessary though.
Mixed a batch mid december and just developed a roll in it last week. That stock solution is still fully water-clear.

If I recall correctly, Kodak states a 6-month shelf life in full bottles without air, but I'm not sure if that is also valid when re-using the developer.

+1

I always mix the 3.8l packs of D76 and store it in a 5l plastic fuel canister. And I add some Protectan or lighter gas in the canister. My last batch is at least half a year old and still usable without problems (one shot only).

It won't last more than a month or two before it goes a little "strange", at least that's my experience. Your bottle is fine, just try to keep the chemicals relatively cool. D76 really doesn't like heat.

You also may have bought a defective bag of developer. My new package of Dektol came out so brown that after mixing it up I threw it out, and my D76 looks like tea (it was mixed just 2 days ago). I emailed Kodak and they're sending me a new packet of D76. The Dektol they didn't mention, so I guess I'm on the hook for that one.

Buzz-01 said:

With re-using your developer, do you develop the film in stock solution and then pour it back in the container for next use?

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I was indeed talking about pouring it back. I guess some oxydation must still have taken place because there was some air in the bottle still as it wasn't filled to the brim.

Ernst-Jan said:

Use some butane (lighter gas) and spray a bit in the bottle, this prevents oxidation.

Click to expand...

This should work, thanks!

momus said:

It won't last more than a month or two before it goes a little "strange", at least that's my experience. Your bottle is fine, just try to keep the chemicals relatively cool. D76 really doesn't like heat.

Click to expand...

Kodak themselves state 6 months. I wasn't fully expecting that but the second batch went bad in less than a week so something must have been wrong. I guess it was the heat though. Thanks for the advise!

I would recommend storing the mixed stock in amber glass bottles with a squirt of Protectan or butane to keep oxygen away from the solution. IMO, using distilled water is the best, too. I wouldn't recommend storing beyond about six months because the pH will rise over time causing more contrast in your negatives. D-76 is a perfectly good developer and it's really cost effective, if you mix it yourself.

I have some 1/2 gal, 1L, and 500mL glass bottles. 1/2 gal is storage. They get filled to the brim. 500mL is the working bottle, subject to re-use. They're usually a little under 500mL, because my tanks are all a little smaller. 1L are intermediate storage, and are filled all the way up. It took me around 6 months to finish my last batch. I didn't detect anything funky about the behavior. My darkroom is pretty consistently 60F through the winter, and it may get up to 64F in the summer.

I have some Bloxygen that I haven't used yet, and also some vacuum tops that have held a seal very well for several months. I'll probably start using them on the 1L's and 500mL's sometime this year.

Any air in the bottle at the top will cause developer to go bad fairly quickly, especially if it's been used before. I use 1-liter plain seltzer bottles (PET plastic is a good oxygen barrier) and squeeze them before capping to eliminate any air. This becomes difficult if you are using the one-shot 1:1 dilution. I use stock D76 solution (4 rolls per liter). With reuse, even with no air in the bottle I found if I developed 2 or 3 rolls, the developer would go bad in about a month, so it's worth making sure you'll use the liter in a reasonable amount of time, even saving up rolls to do so.