Help, my phal buds wither and fall
 

hello,
i am a new member and wanna say "hi" to everyone but im not a begginer with orchids. i have had two of my five phals for more than 4 years.
i cared for them very carefully and they expressed their gratefulness through growing and blooming every year!
now i have a problem with one of them. and i cant think of any solution. i tried everything.
several months ago i repotted the orchid - i did not repot it for the 1st time - cause it filled the old pot with roots and the leaves got extremely big and after i repotted it the orchid looked even fresher, healthier and happier with the new fresh compost and bigger pot.
the last time it bloomed the orchid had two stems and they did not dry so i did not cut them. and the old stems started growing again and new branches appeared. after the branches the buds came - about 30!
i started watering with fertilizer every week. when some of the buds got very big they suddenly started to turn reddish, then withered and finally fell. at first only 4 or 5 fell and i did not bother very much, but now out of 30 buds only 4 or 5 remained.
nothing has changed in the way i look after the orchids. they are next to a west facing window, i water them once in the week now since it is winter here in bulgaria, i hold the pots in water for about half an hour and then pour the water out. when they are not to bloom i fertilize them once every two weeks, but when the stems and buds appear i fertilize every two weeks. i have a sprayer and spray the leaves 2-3 times a day, and my orchids have two dishes under the pot - one deep for the water to gather when i water them, and one dinner plate in which i pour water when im not home so the water can evaporate without reaching the roots. the pots are plastic and transparent with large holes i pierced on the bottom of the vessel i used as a pot, since my orchid got so big, that i could not find big enough pot for it. i regularly check the roots for any signs of rot, but they are just OK. i checked the leaves for rot or parasites, but the are OK too. something more - a new stem appeared so if the orchid was ill or something was wrong with the conditions in which i look after it i suppose the stem would not grow at all. the temperature is never below 20 degrees Celsius, during the day is about 30. the compost i use is pine chopped bark. do i miss something? or i do something wrong? but have looked after it for 5 years and it bloomed every year. and now i just cant understand whats going on.
to make the things worse, my second phal's stem had one bud and kept on growing when the bud first turned yellowish, then withered, after that turned black and the stem stopped growing and its top is turning brownish.
if anyone can think of a solution, pls, help!
thank you!

If you have a phalaenopsis, I recommend you visit the Beginner forum and read all the posts on the sticky - "The Phal Abuse stops here". Great info for anyone growing this genera.

I had a similar experience and found that the evaporative tower humidifier I had just bought was creating a breeze of cooler air in the strangest places. I moved it further back and all the other buds are now OK. So -if I was you I would look to see if there is any draft of any kind as a first step.

thanks for the advice ppl!