Quote Originally Posted by Michael R View Post
Thiosulfates are more stable in air than say developing agents, but they do oxidize. This is one reason why even neutral (eg TF-5) and alkaline fixers contain sulfite to scavenge oxygen. In general, plain air is not the best idea for gas burst agitation in a B&W process. If you want maximum longevity out of your TF-5 with a re-use regimen, nitrogen would be the way to go. Alternatively if you stick with air, test your fixer at regular intervals. Using air will accelerate oxidation, but how much faster, we don't know. It may or may not make a meaningful difference in how long you normally run a batch of TF-5. All you can do is monitor it.

Hope this helps.
Yes, that helps.

Thank you!