As far as I know, the cause to purple stains in T-MAX negatives is the insufficient removal of the anti-halo dye. This evenience normally implies a non-perfect fixing action. This is mainly due to the T-Grain structure of T-MAX films: in Tabular Grain films the silver halyde grains are literally smashed and flattened before the emulsion layer is coated onto the plastic film. As a result, the emulsion layer is far more compact than normal, and the fixer has difficulties in penetrating the gelatine: its action is far slower than normal.(posted 9668 days ago)Just to report a "rule of thumb", with T-MAX films you should use a fixing time double than that suggested by the fixer's manufacturer for "normal" films. A further safety rule is to consider the exhaustion rate of the fixer to be doubled (1 TMAX film = 2 normal films).
Films showing heavy purple staining can be successfully re-fixed and re-washed. If the staining is light, probably a long re-wash in running water (30 min. or so) will suffice.
I normally use Ilford Hypam fixer at film strength for 6 minutes (about three times the suggested time); at this point my negs show a very light purple staining that disappears in the first 5 minutes of my standard 30 min. wash in running water.
Happy new year
Carlo