Hello all, beginner Peristeria elata in trouble!

[noseque82]

Hey guys and girls, I'm not much of a blogger, and upon suggestion from my husband I found this forum to see what i could learn from those with more experience than I seeing as how my main orchid guy is no longer with us. I have two Peristeria elata or white dove orchids for about a year and a half now. when i originally got them they had tall beautiful fern like leaves, nice healthy large bulbs and growing vigorously. It is now a year later, and I'm afraid that my inexperience has taken it's toll. I am willing to take any and all steps necessary to bring these guys back from the brink. these photos are fresh from this morning after watering. as you can see, the original bulbs are wrinkling and browning and the roots are rotting or shrinking away. the new bulbs growing out of the old ones are now starting to look unhealthy. can we remove these new bulbs and repot them? What can i do to bring these guys back to life!!!

I water once a week. and mist lightly twice a week.
feed them once a month
they are sitting in an orchid medium cocoa coir lava rock and cocunut husks they are sitting loosely in the pots, in an easterly facing window that gets bright indirect sunlight all morning and part afternoon. temperature stays fairly consistent between 70-80

I'm originally from panama and would be ashamed if I let them die!

Thanks