I have develop old "no name" (bulk) ortho 135 film with fresh POTA and fresh TF-2.When film was still wet there was plenty small particles (0.1-0.3 mm) all over film.Can't be crystals because fresh chemistry (14 hrs).After short investigation conclusion was that perforating machine didn't work properly and there is a still particles in perforations.Good point is that there is no scratches on film. Never saw this before.
If its from bad perforation be careful using it in cameras as bits can jam a shutter.
Best thing you can do now is try a very agitated pre rinse before dev, to remove as much as possible to prevent those particles messing with development because of surface contact.
Negatives are ok, because this particles sink on the bottom during developing.When I finish with fixer than they stay on the wet film.It is bulk film so it is possible to clean before put in to spool.
I haven't notice any particles until I hang wet film.There was a still particles in few perforation because perforation machine didn't cut properly.But like I said it's ok because negatives are clear from scratches.
But if there are loose particles arround, they may have landed on thefilm surface beofre exposure thus causing a blank spot in the image becasue it did net get exposed as the speck was blocking the light.
I have found some particles in film loader,few in camera and the rest of particles are separate from perforation during developing.I have testing one film with POTA and Rodinal and both piece of film are ok.Just lucky :confused: