I've heard that dehumidifier water is bad bad bad. Because of the amount of bacteria and other little buggies that grow in it.
I use the Ilford wash method, modified on three counts. First, after the first wash, I give the film two minutes in a hypo clearing agent. I know you don't need to do this for film, but it can't hurt. Then I do agitation cycle, except I usually agitate more (20, 25, 30 instead of 5, 10, 15), and I let it sit for a 30 seconds or a minute after each agitation cycle. During this period I start cleaning up the bathroom a bit (wash funnels, etc.)
Seems to work so far (knock on wood).