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Darkroom - prevent oxidation in chemistry

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Photoemulator

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A number of years ago, there was a thread about using an inert foam lid to prevent the chemistry from oxidizing too quickly in large reservoirs. I was thinking about water bags or even, if you have a tank with a lid on top, floating some foam there. Does anyone have experience or other suggestions???
 
I believe the usual approach is to use concertina bottles & expel the excess air after use. It's the only approach I've used in the darkroom.

For more reactive compounds in the lab we would store them under nitrogen & extract reagent via a syringe without opening the bottle. I don't think that's necessary for photo reagents
 
For those of us whose Bordeaux collection will outlive them, nitrogen spray in a can. When we cannot finish a bottle, which is always, use nitrogen in a spray.

À votre santé
 
CO2 is heavier than air...you could blow that into the bottle before capping it. CO2 is cheaply available for making sparkling water!
 
I'm experimenting with pure argon canisters, sold for wine preservation purposes. I purchased the least expensive version, Airgone; but another conspicuous brand is Bloxygen.
 
I just use empty plastic drink bottles (washed out) and scrunch them up as developer is used to keep the level of liquid at the top.
 
Floating lids are used in large tanks. Kodak made 1/2 up to 3 1/2 gallon hard rubber tanks with floating lids. Doran/Premier make round storage tanks 2 to 5 gallon with a floating lid and a separate dust cover. These work great. Look at B&H for storage tanks etc.
 
Another good method is to buy a box of wine and when empty take the bag out of the box, remove the tap and wash it out. Then fill with chemical, replace tap. Cut the box to reverse it inside out and replace bag and mark box with contents. Hey presto, container with spring loaded tap to avoid wastage and bag collapses as used.
 
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I believe the usual approach is to use concertina bottles

I recommend against these bottles as strongly as possible.
They are extremely difficult to remove residue from, and they often start leaking through the folds.
 
I am another fan of StopLoss bags. They are efficient once the air has been expelled, which is easy to do.
 
Over the long run, all those thin plastic camera store style containers prove permeable to oxygen. Actual glass is way better, or at least thicker virgin plastics designed for serious chemical storage.

My no. 1 culprit is Part B of RA4 developer concentrate, which goes bad before the other components once it's opened. Being able to preserve this over a few months of color printing inactivity would save me a lot of money. They don't sell this specific component by itself anymore.

And I can't exhale into these kinds of solutions or even work in proximity to them without highly effective fume exhaust ports directly above the bottles themselves. They're not like ordinary B&W chem.
 
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