Update. So, as I stated before, I switched over to tap water until my CalMag came in (which took about a week). This turned out to be a very bad idea. By the time the CalMag came in, the roots weren't looking to good, they had gone from white to somewhat brown, and from firm filaments to kind of mushy.

When I flushed out the bad tap water and went with new distilled+CalMag, I tried to flush the roots as best I could. It didn't seem to do much good, the mass just stuck together. I held out hope that the fresh water would help.

After 1 week with CalMag, the plant was looking better. There were about 8 spots with new growth, and by the end of the week all of them had begun to flower. However, the roots looked worse. There was some new root growth to the side of the original mush-ball which looked actually good, nice and white with spurts of side-growth. I did some searching and found a couple of threads where it was suggested to prune the root rot.

I did this last night after changing out the water again, leaving the new root growth intact the best I could. I'm a little worried about it because the root pruning at this stage, because the flowering sites looked good, and I didn't want to set those back in development, but I didn't want that root rot to spread to the new root growth either.

I will definitely say that this is the last time I use my tap water. In fact I might even quit drinking it!