Thank you all for the response. I think its the sudden change in temperature and moisture that is to blame. There was a sudden drop of temp. from 28C to 18C and the humidity dropped from 58 to 42%. I have created a mini g/h out of plastic shelves and plastic bags for the paphs and some of my smaller phals. We'll see if it works, so far, I don't see any sign of rotting yet.