Phal roots help, please

[VickiC]

Hi,
Yesterday when I bought a Den, I also bought a Phal. I am in the process of repotting my new Phal now. I have photos attached of the roots, but the pictures are not good...I apologize. It's the best I could do at the time, though. Even so, hopefully you can see enough to help me with my question, which is: If a root growing from the stem is healthy, but farther down the root has rot.....and then farther down from that is healthy to the end, what should I do when trimming? Should I remove the entire root (since there is rot in one section), or trim from the rotted area to the end (even though the end is healthy)? If not, where?

Also, as you can see, I haven't finished rinsing the old sphag from the roots.....but after I do this, should I soak them in Physan 20, peroxide or something else, and THEN trim the roots.....OR should I trim the roots THEN soak it in something.....or not soak it at all? If you advise treating the roots with a solution, what do you suggest I use for a fungicide?

I know there is most likely a simplier, easier to understand and less wordy way to compose my question to you.....but I am rushing around in a hurry (which is quite common for me lol).....and I don't have the time to compose my post better.....I'm sorry.

I would very much appreciate your advise.
Thank you in advance,
Vicki