I know that wash aid is not required with TF5 or 4, but it is a habit with me that I just continue. I simply mix up a little sodium sulfite to immerse my prints in for 3 minutes after the second fix, then into the washer. After 20 minutes they test clear of fixer. I figure that the few cents I spend on sodium sulfite is offset by water savings. This is for untoned, selenium toning, or any other toner.