Can I use the ilford washing method with Kodafix since it is a hardening fixer?
Are you asking about prints or film?
The Ilford archival FB print sequence requires a non-hardening fixer. Even so, it doesn't always work for all papers though Ilford tests it with theirs. Film is much easier to wash clean (more akin to RC paper) and might work with the Ilford fill and dump method. You'd just have to test for residual hypo and try it.

