The humidity has been good and not too wet.
I know this because I've been in the tank a number of times, moving plants around and such. When I dug up one of the masd. the mix was moist but not wet and it was very fluffy. . .big chunks of bark chips.
I am thinking that the shelving unit below is catching any extra water. So the roots are not wet, really only slightly damp. What I am really worried about is that there is not enough air cirulation around the roots. . . like there would be if they were mounted.
I just received my cooling fan in the mail today. I've put it in the tank and hopefully that will help too.
This will be a real test and I plan to make any changes needed. . .I'll be keeping a close eye on the plants health.