I re-use all film fixer many times until the clearing times get longer than about 45 seconds. All my film sits in fixer for 2.5 minutes. I've never encountered any problems. I use Ilford Hypam for all film and printing as it's non hardening.

For printing, I use ilfords two bath system diluted 1:7 for each bath. I fix FB prints for 1 minute in each bath. When the printing session of no more than 12 prints is complete, I throw away the first bath, and reuse the second bath as the first bath in the next printing session. Seems to work well, and good economy etc. I've never had a problem with staining or issues with toning washing etc.