my system is ,I develope my roll of film with fresh chemicals I keep the fixer ,then I print my photos with new paper developer and some of the old fixer , I buy my dev/fix in 5L bottles as its 1x9 for dev I am not to fussy ,I am a bit more careful with the fixer ,as long as you don't over use it I cannot see any problem keeping diluted developer that you have used only a little bit we have all done it (most of us) good luck
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