I reuse my fixer all the time. I have done this with both Ilford and Kodak fixers. You probably should not be using a hardener for paper prints. Not sure what effect the hardener has on storing fixer after usage. Besure you store the non-hardening fixer in a bottle w/cap.(posted 8932 days ago)I would re-fix your prints, and wash them again as you normally would. Under-fixed prints will go bad in time. By the way. What strength are you mixing your fixer (i.e. ration of water to fixer).