While they should definitely change if aspen is giving them respiratory issues it’s certainly a fine substrate for a BP if your local climate is amenable.
I live in Mississippi and have had more issues with mold using coconut husk substrate than aspen. I can get either option to work for me but I change depending on the season and personal preference at any given time.
During the summer aspen works great and I often don’t even need to mist during sheds and have no problems.
Sent from my iPhone using Tapatalk