From a chemical standpoint, the silica will be essentially inert, but it is in the form of a very fine powder which will be rather difficult to completely remove. (That's sili
con dioxide, by the way; the other stuff is for enhanced development of Hollywood starlets, not film
) If you are making 8x10 contact prints, it won't matter; if you are working with Minox film, it will. In between, settling the solution and filtering before use may be adequate, even if it doesn't get out the colloidal particles.
Since citric acid is cheap and mailable, it might be better to just go with a non-household product from PF or some other supplier.