You may also be picking up more crud in the other processing solutions. If you are picking up a bit of oil or grease on the way then problems will get compounded.
Mix up a new batch of rinse for each roll(s) using distilled water and discard after use.
I pre-dilute Photo Flo 1:20 with 95% isopropyl alcohol (add 3/4 oz Photo Flo to a 1 pint bottle of alcohol) and then dilute it again at 1:20 with distilled water just before use. The end result is using it at about 1/2 strength but the 5% alcohol in the final rinse adds a small amount to the sheeting action and so the action comes out about the same. Soak the film for about a minute. As mentioned by another poster, after hanging the film I wet my fingers in the rinse and gently squeegee the excess water off the film.
The film should appear uniformly damp. There should be absolutely no beading. If there is then return to the Photo Flo for a longer soak.
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