Gads..I should put this on a macro; I've written it at least five times this week.(posted 8995 days ago)The purple stuff you see is leftover sensitizing dye and can safely be ignored. It'll fade over time.
But if you must get rid of it...
There's NO NEED to fix the film practically forever.
Use a _rapid fixer_ for three to 6 minutes, depending on temperature, with _constant agitation_.
After fixing, rinse in a wash aid for two to three minutes. The wash aid can be the store-bought stuff or you can make your own by dissolving a tablespoon of sodium sulfite in a quart of water. (25g/liter)
Agitate continuously in the wash aid.
Then wash normally, 20-30 minutes in an efficient washer, use wetting agent and dry normally.
T-grain films, and Ilford's equivalent core-shell types, will still be left with just a hint of the magenta or often none at all.
With all films, you really should be giving constant agitation in the fixer, whether ordinary or rapid, and using a wash aid anyway.