Help! With root problems, repot, newbie and Phals Just add ice

[Cutiedeer]

Please help me identify what roots need to be snipped with sterilized scissors and what can stay; what problems I have (?fungus, root rot, etc ) and how to treat. I have had most of these for a few months, bought on clearance for $1 each. I have known that I need to report but the first bag of miracle grow orchid mix was full of gnats. I know they are Phals and particularly sold by the JAI. I have finally got around to buying a miracle grow orchid bark bag that is not full of gnats. I plan to sterilize the pots today in a mix of dilute bleach water. I have new 6 in (slightly shallower) clear pots/liners to report them to, but they won't fit any sturdy pots (clay etc they came in). I have lost two already, a few weeks ago. The leaves started getting a circular mosaic spreading yellow pattern on them and I haven't found any pics online that look quite like that. I read cinnamon was good for fungus so I put that on any cuts, and the top level of roots where there was a bit of very tiny white fuzzy stuff. Yes, I now know I probably aided their swift death. I had a few orchids years ago that got a mealy bug infestation. I want to do well to these six guys left. I have read about Physan- and there are some other treatments I've seen (dilute bleach and soap mix, listerine) but I don't know how and when to do them. Last night I just picked out all the moss packed super tight in 4, and some light bark in two. All came from same store I work at. Some were labeled waterfall if that means anything. So, last night, I picked out the medium, ran them under room temp tap water for 15 seconds, and am letting them "air out until I repot tonight. I am also soaking the bag of orchid mix. I have some miracle grow acid loving fertilizer- how and when should I apply this after repot? Thank you so much for all your help. Sincerely, newbie trying to keep them alive.